Patent 0 ICC Patented Aug

2,849,470 United Patent 0 ICC Patented Aug. 26, 1958

Qua! 2 with a substantially equirnolar proportion of a salt of the 2,s49,470 desired transition metal of groups VI to VIII. The following examples in which parts are by weight‘ OXY-DECYCLOPENTADIENYL COMPOUNDS OF are illustrative of the invention. TRANSITION METALS 0F GROUPS V1 TO vm AND THEE PREPARATICN EXAMPLE I Richard Edward Benson, Claymont, DeL, assignor to E. 1. Part A.—Prep.flrati0n 0f bis(]-benzoyloxy-3-methyl du Pont de Nemours and Company, Wilmington, DeL, cyclopentadienyl ) iron a corporation of Delaware To a vigorously stirred suspension of 16 parts of No Drawing. Application August 6, 1954 sodium amide (from 9.4 parts of sodium) in about 200 Serial No. 448,371 parts of anhydrous liquid ammonia in a glass reactor ?tted with a sealed stirrer and a re?ux condenser cooled 25 Claims. (Cl. 260-439) with solid carbon dioxide/acetone was added dropwise over a period of 20 minutes 19.2 parts (0.5 molar pro This invention relates to a new class of organometallic " portion based on the sodium amide) of 3-methyl-2-cyclo compounds and more particularly to the hydroxy-substi pentene-l-one while maintaining the reactor at about tuted derivatives of organometallic compounds of tran -—33° C. A red-brown solid formed at once and after. sition metals of groups VI to VIII, inclusive, of the stirring the reaction mixture for one hour at this tem— periodic table. perature, 12.7 parts (0.5 molar proportion based on the Organometallic compounds, in which the metal is di 3-methyl-2-cyclopenten-l-one) of anhydrous ferrous chlo recting linked to one or more organic radicals through ride was added in small portions over a period of 15 carbon thereof, are not only of interest from a theoretical minutes. The resultant black reaction mixture was held standpoint but also have many practical applications. at —33° C. under re?ux with stirring for an additional Thus, tetraethyllead is widely used as an antiknock agent 75 minutes. No further solid carbon dioxide was packed for internal combustion engines, and many mercury com 25 into the re?ux condenser and approximately one-half of pounds have found use in the fungicide and/or pesticide the liquid ammonia was permitted to evaporate through art. Many organometallic derivatives of the elements the condenser. The remaining liquid ammonia was dis of groups 1 and H of the periodic table have found funda placed by the addition of about 175 parts of anhydrous mental use in chemical syntheses, both as reactants and diethyl ether. The resulting black ?uid reaction mixture catalysts. Until quite recently, however, very little was was allowed to stand overnight under nitrogen at room known concerning any stable organometallic compounds temperature and then about 90% of it was poured under of transition metals of groups VI~VIII of the periodic nitrogen into 250 parts of deoxygenated water contain— table. ing eight parts of sodium hydroxide. After brief stirring Dicyclopentadienyliron has been prepared (see Kealey the resultant black solid was removed by ?ltration under and Pauson, Nature, 168, 1039 (1951), and Pauson, 35 nitrogen. The red-yellow ?ltrate thereby obtained was U. S. Patent 2,680,756) as have also some derivatives shaken with cooling with 24 parts of benzoyl chloride and of this interesting organoiron compound, for instance, cer the resultant yellow-orange solid removed by ?ltration. tain diacyl derivatives and the dicarboxylic acid [see After washing with 1% aqueous sodium hydroxide solu Woodward et al., J. Am. Chem. Soc. 74, 3458 (1952)]. tion, dilute sodium bicarbonate solution, and ?nally with ‘ Other cyclopentadienylmetals have been made, e. g., di 40 water, there was obtained after drying 15.3 parts (34% cyclopentadienylnickel (Thomas U. S. Patent 2,680,758), of theory) of crude bis(1-benzoyloxy-3~methylcyclopenta- ‘ dicyclopentadienylruthenium (Wilkinson, I. Am. Chem. dienyl)iron as a yellow-orange solid. After recrystalli- ‘ Soc. 74, 6146, 1952), and dicyclopentadienylcobalt (III) zation from glacial acetic acid, the pure bis(l-benzoyl salts (Wilkinson,'ibid., 6148). These various compounds _ oxy-3~methylcyclopentadienyl)iron was obtained as ?ne, are of special interest in many ?elds, such as antiknock yellow-orange needles, melting at 121.5-1235" C. and‘ agents, fungicides and pesticides and as intermediates to soluble in ethanol, methylene chloride, acetone, and still other interesting and desirable organometallic com diethyl ether to give yellow-red solutions. pounds. Analysis-Calculated for C28H2204Fe: C, 68.7%; H, This invention has as an object the preparation of 4.9%; Fe, 12.3%. Found: C, 68.9%; H, 5.0%; Fe, new organometallic compounds. A further object is the 12.5%. preparation of new resin intermediates. Another object The crude product obtained above was a mixture of is the preparation of new photographic developers. Other two stereoisomers which are separable by fractional crys objects will appear hereinafter. tallization. Thus, after several recrystallizations from These objects are accomplished by the present inven acetic acid, the bis(1-benzoyloXy-3-methylcyclopentadien tion of dicyclopentadienylmetal compounds wherein one 55 yl)iron was obtained as ?ne yellow crystals, melting at atom of a transition metal of groups VI to VIII, inclusive, l23.5-125° C. After fractional crystallization of this of the periodic table is directly and singly bonded to material from n-heptane the high melting isomer (A) two cyclopentadiene nuclei, each carbon of which nuclei of bis(1-benzoyloxy-3-methylcyclopentadienyl)iron was is a member of but one ring, through nuclear carbon obtained as thick clusters of ?ne, yellow-orange needles of said nuclei, at least one of said nuclei having a nuclear 60 melting at 125.5-127" C. The acetic acid ?ltrates from carbon thereof singly and directly bonded to oxy oxygen, the previous recrystallizations were combined‘ and‘con i. e., to hydroxyl, or salt, ester, or ether thereof. centrated. Upon standing yellow-orange crystals of the This new class of compounds can conveniently be low melting isomer (B) of bis(1-benzoyloXy-3-methyl prepared by the process wherein a ?ve membered mono cyclopentadienyl)iron separated and after isolation by nuclearly unsaturated, carbocyclic ketone having at least 65 ?ltration were found to melt at 99-103“ C. After frac two hydrogens on annular carbon wherein the carbons tional crystallization from n-heptane as described above, , of the carbonyl containing, 5 membered ring are mem (B) was obtained as ?ne, long yellow-orange needles, bers of that ring only, i. e., a cyclopentenone, are metal melting at 104-105" C. Addition of approximately 5% lated by bringinc7 the ketone in contact with two molar of the high melting isomer (A) to the low melting isomer, proportions of an alkali metal amide in liquid ammonia 70 (B) depressed the melting point to 99-103" C. and the resulting dialkali metallated product is reacted Analysis.-Calculated for C26H22O4Fe: C, 68.7%; H, 2,849,470 ~ 3 r v 4.9%. Found [for thehigh melting isomer (A)]: C, "methylene chloride and insoluble in carbon tetrachloride, 69.0%, 69.0%; H, 5.0%, 4.8%. Found [for the low n-heptane, and petroleum ether. Sublimation at 130 melting isomer (B)]: C, 69.2%, 69.1%; H, 5.0%, 5.0%. 140° C. under a pressure corresponding to 0.1 mm. of The infrared spectrum of a sample of the above low mercury in open ended glass vessels aiforded the pure melting, . isomer of : ,bis ( 1-benzoyloxy-3jmethylcyclop enta bis(l-hydroxy-3~methylcyclopentadienyl)iron as an or dienyl)iron,~,determined in carbon tetrachloride solution, ange-yellow solid, extremely sensitive to air. exhibitedstrong absorption bands at 3_.25,u., 3.4a, and The infrared spectrum of the pure bis(1-hydroxy-3 5.76,Ir which three bands are ‘characteristic, respectively, methyl cyclopentadienyl)iron determined as a mull in for unsaturated C—H linkages, i. e., hydrogen bonded to hexachlorobutadiene exhibited strong absorption. bands an unsaturated carbon," saturated C-H linkages, i. e., 10 at 3.25” and 3.411., which bands are characteristic, re hydrogen“ bonded ._to saturated carbon, and ester type spectively, for unsaturated C-H link-ages, i. e., hydrogen carbonyl linkages; The spectrum. also exhibited strong bonded to unsaturated carbon and saturated C-H link absorption bands at 6.751;, 6.9,u, 7.3”, 825p, and 8.35”, ages, i. e., hydrogen bonded to saturated carbon. The as well as several weaker bands, particularly at the longer spectrum also exhibited strong absorption bands at 3.0;r, wavelengths. These ‘observations are consistent with the 15 3.7,“, and 3.9”, which three bands are characteristic for sandwich structure. hydroxyl and similar to that of phenol. As in the case “To a solution of 3 parts of potassium hydroxide in of the preceding diester, the spectrum of the hydroxy about ‘40 parts of methanol was. added 2.3 parts of an compound also exhibited additional sharp bands, par othervsample ‘of the above-described mixture of stereo ticularly vat the longerwave lengths which observations isomers of vbi_s(l-benzoyloxy-3-methylcyclopentadienyl)— 20 are consistent with a sandwich type structure. iron; The resultant orange solution was boiled for about 5 minutes during which it became green. About EXAMPLE II half the methanol was evaporated and the residue diluted Preparation of bis(1-hydroxy-3-methylcyclopentadienyl)— with about, 75-80 parts of freshly boiled distilled Water. cobalt (III) reineckarte Acidi?cation of the resultant light green'solution resulted 25 in a voluminous. precipitate which redissolved on the addi To a vigorously stirred suspension of sodium amide tion ‘of 5% aqueous sodium hydroxide to bring the pH to (from 10 parts of sodium) in about 200 parts of liquid ammonia in a reactor Similar to that described in Exam 10. The solution was used as a developer for a com mercial, Fine Grain .Release Positive ciné ?lm as follows: ple I was added dropwise over a period of 20 minutes 30 19.2 parts (0.46 molar proportion based on the sodium amide) of 3-methyl-2-cyclopenten-l-one. A red-brown ' Exposure Develop- Result ment solid was formed at once and the reaction mixture was stirred for 45 minutes at the re?ux. Anhydrous co A. White light- ____'______30 seconds- Very dense. baltous chloride (13 parts—0.5 molar proportion based B. Short (quick ?ash/t0 room 1 minute__ Low density, plus fog on 1ights—475 seconds). unexposed portion. 35 on the 3-methyl-2-cyclopenten-l-one) was added in small 0. Short (same as B) ______3 minutes. H§gher density plus greater portions with stirring over a period of 10 minutes. The - ~ 0g. To the ‘ same solution was resulting black react-ion mixture was stirred at —33° C. . added 10. parts oi‘ sodium under re?ux and under an atmosphere of nitrogen for metabisul?te and the fo1low~ in'g tests made: ' , 2.5 hours. No further solid carbon dioxide was packed D.‘ Short. (same as B) ______1 minute__ Low density plus fog. 40 into the re?ux condenser and approximately one-half of E. Short (same as B)__.__'_-__ -__do ______Do. . the liquid ammonia allowed to evaporate through the unpacked condenser. The remaining liquid ammonia The last test was made after the developer had remained was displaced by the addition of about 175 parts of an standing overnight tightly stoppered. hydrous diethyl ether and the resulting mixture was then The data reported in entries B and C show that the 45 allowed to stand under an atmosphere of nitrogen over above compound of, this invention functions as a selec night. A solution of 350 parts of deoxygenated water tiveideveloper with increasing development time in that containing 25 parts of sodium hydroxide was added and it preferentially-acts on the exposed areas of the ?lm. after brief stirring the solid was removed by ?ltration The ‘data in entries D and E show the relatively long under nitrogen. The resulting yellow-red ?ltrate was range stability of the compounds of the present inven 50 acidi?ed to litmus with hydrochloric acid and approxi tion asregards theirdevelopment action. The fact that mately 20' parts of 3% aqueous hydrogen peroxide was the same degree of development .action is also exhibited added, followed by an excess of an aqueous solution of , by the compound of this invention after standing over Reinecke salt lNH4Cr(NH3)2(SCN)4.I-I2O]. The result night is .to be contrasted with the extremely short-term .ant orange-brown solid was removed by ?ltration and life of many present-day commercial developers. ‘ 56 after drying there was. thus obtained 3.5 parts (6% of Part B.-~Preparation of bis(1~hydroxy-3-methylcyclo theory) of the crude bis(1-hydroxy—3-methylcyclopenta pentadienyl?ron dienyl)cobalt (III) reineckate as an orange-brown pow der melting at l54—157° C. with decomposition. After _To a solution of 60 parts of absolute alcohol and 15 recrystallization from acetone/water the pure product parts of water, which had been re?uxed for ?ve minutes 60 to remove any absorbed air, was added three parts of was obtained as an orange-brown powder melting at the above .bis(l-benzoyloxy-3-methylcyclopentadienyl) 154~l62° C. (dec.). The melting ‘point range is due, as iron. The system was thoroughly ?ushed with nitrogen pointed out in Example I, part A, to a mixture of stereo isomers. , > " and two parts of aqueous potassium hydroxide was then Analysis.—Calculated for added. After re?uxing the resulting red solution under 65 nitrogen for 1.5 hours, the alcoholwas then removed by 33.9%; H, 3.6%; N, 14.8%. distillation, additional deoxygenated water was added, 3.9%; N, 14.5%, 14.8%. and the solution was allowed to cool to room temperature The foregoing examples .aremerely illustrative and the under nitrogen. Upon acidi?cation with hydrochloric invention is generic to oxy-dicyclopentad-ienyl deriva tives of transition metals of groups VI-VIII, wherein at acid, a yellow-orange solid formed which was removed‘ 70 by ?ltration under nitrogen. 1 After being washed with least one oxy group is attached directly to nuclear car bon of at least one of the cyclopentadiene rings and deoxygenated water and a dilute aqueous sodium bicar wherein the cyclopentadiene ring carbons are annular bonate solution prepared from deoxygenated water, the members of only one ring. Because of readier avail crude bis(1~hydr0xy-3-methylcyclopentadienyl)iron was ability of the necessary intermediates and greater ease obtained after drying as a yellow-orange solid, soluble in in preparation,’ the preferred compounds are solely hy 2,849,476 5 . . 6 drocarbon in nature, other than hydroxyl (and esters, (cyclohexylcyclopentadienyl)(1 - hydroxy - 3 - methyl ethers, and salts therethrough), the transition metals of cyclopentadienyl)manganese, etc. groups VI—VIII, and inorganic acid anions as and when Thus, this invention is generic to the ‘hydroxydicyclo needed to satisfy the valence of the transition metal. pentadienyl and nuclear hydrocarbon-substituted hy Thus, this invention includes in its preferred aspects the droxydicyclopentadienyl derivatives of transition metals nuclear, mono-, di- or polyoxy derivatives of the dicyclo of groups VI-VIII, wherein the ring carbons of both pentadienyl metal and the alkyl, aryl, cycloalkyl, aralkyl cyclopentadiene nuclei are annular members of only one and alkaryl nuclear hydrocarbon-substituted dicyclopen ring and wherein at least one of the said cyclopentadiene tadienyl compounds of groups VI-VIII, and especially rings carries at least one hydroxy substituent directly group VIII, transition metals and the inorganic acid salts 10 linked to nuclear carbon thereof. These hydroxy-sub thereof through the transition metal. stituted dicyclopentadienylmetal compounds are highly The new hydroxy-dicyclopentadienylmetal compounds reactive and are normally isolated, puri?ed, and prefer of this invention are represented by the following struc ably handled in the form of their ethers, esters, and salts, tural formula: to which the invention is likewise generic. The ethers 15 include those derivatives wherein the hydrogen of the hydroxy group on the cyclopentadiene ring or rings has been replaced by a monovalent wholly hydrocarbon radi cal free of aliphatic unsaturation and including the ali phatic, aromatic, alkaromatic, araliphatic and cycloali 20 phatic monovalent hydrocarbon radicals, e. g., methyl, propyl, benzyl, cyclohexyl, cyclohexylmethyl, phenyl, tolyl, and the like. The monovalent saturated hydro carbon radicals of no more than seven carbons are pre wherein n and n’ are cardinal numbers, alike or different, ferred. The esters can be those of any organic mono and in each instance no greater than 5, with the sum of or polybasic acid and are preferably those of the wholly n and n’ being at least 1; R and R’ are hydrogen or hydrocarbon carboxylic acids free of aliphatic unsatura monovalent, solely hydrocarbon radicals, alike or differ tion, including the aliphatic, aromatic, alkaromatic, arali ent, e. g., alkyl, aryl, cycloalkyl, aralkyl, or alkaryl rad phatic and cycloaliphatic monocarboxylic acids, e. g., icals, each usually of no more than seven carbons, and acetic, propionic, benzoic, toluic, phenylacetic, cyclo preferably free from aliphatic unsaturation and most 30 hexylacetic, cyclohexanecarboxylic acids, and the like. preferably of no more than four carbons apiece; M is a Acids of no more than seven carbons are preferred. transition metal of groups VI—VIII, and especially group The salts through the hydroxyl group or groups can be VIII, of the periodic table, preferably in the ?rst long those with any salt forming metal of which the alkali and alkaline metal are the most usual. The salts through period thereof; In is a small cardinal number generally 35 not greater than 2, as required to satisfy the valence of the transition metal of groups VI-VIII can be those said metal M; and X is an inorganic anion such as halide, with any of the salt-forming acids, such as the mono-, nitrate, bromate, sulfate, phosphate, sulfonate, carbonate, di-, or tri-basic simple mineral acids, e. g., the hydrohalic ferricyanide, and the like. The R, R’, and OH groups acids, sulfuric acid, phosphoric acid, and the like, or the complex-forming inorganic acids or their soluble salts, can be on any or all ?ve carbons of each or both of the 40 cyclopentadiene rings provided always there is at least such as the alkali and alkaline earth metal salts, the ammonium and substituted ammonium and amine salts. one OH group on at least one of the said rings. Prefer Suitable speci?c examples of such complex salt-forming ably, the sum of n and n’ does not exceed two and most compounds include the polytungstic and heteropolytung preferably at least one R or R’ group on at least one of stic acids, e. g., polytungstic acid, phosphotungstic acid, the cyclopentadiene rings is other than hydrogen, i. e., 45 and the salts thereof, e. g., ammonium phosphotungstate; wherein at least one monovalent, solely hydrocarbon sub the polymolybdic and heteropolymolybdic acids, and the stituent is present on at least one of the cyclopentadiene salts thereof, e. g., sodium silicomolybdate, ammonium rings. The invention also includes the esters, ethers, and phosphomolybdate; the Reinecke salts; and the like. salts, through the hydroxyl group, of the above hydroxy compounds. In some instances the combined ester/salts are most useful or most convenient to isolate. In these com The invention includes, in addition to the hydroxy pounds the nuclear hydroxy groups are linked as above cyclopentadienylmetal compounds of the above examples, described to acyl groups, preferably carbacyl groups, in mono- and polyhydroXy-substituted dicyclopentadienyl the well known ester linkage and in addition the transi metal compounds wherein there are no other substituents tion metal of groups VI-VIII is linked in ionic salt on either of the cyclopentadiene rings, such as bis(hy 55 bonds with one of the aforesaid salt-forming acids, such droxycyclopentadienyl)iron, cyclopentadienyl(hydroxy as the simple sulfates, or preferably the complex-forming cyclopentadienyl)i r o n, b i s(hydroxycyclopentadienyl) inorganic acids. Suitable examples of such ester/salts chromium, bis(1,3-dihydroxycyclopentadienyl)iron, etc., are indicated above, an illustration of such a compound as well as the hydroxy-substituted dicyclopentadienyl of this invention being bis(1-benzoyloxy-3-methylcyclo metal compounds of the transition metals of groups VI 60 pentadienyl) iron (III ) tetrabromoferrate. VIII wherein one or both the cyclopentadiene nuclei As illustrated in the examples, the free hydroxy-sub carry one or more aromatic, aliphatic, araliphatic, al stituted cyclopentadienylmetal compounds can be regen karomatic or cycloaliphatic substituents in addition to erated from these esters by simple base hydrolysis or at least one oxy substituent, e. g., bis(l-hydroxy-3-meth from the salts, through the hydroxyl groups, by mild acid yl-cyclopentadienyl)chromium, bis-(l - hydroxy - 3,4-di 65 hydrolysis. Frequently the free hydroxy compounds are phenylcyclopentadienyl)manganese, bis( 1,3 - dihydroxy best obtained from mild acid solution following basic 2,4 - diphenylcyclopentadienyl)iron, bis(l - hydroxy - 3 hydrolysis. The free hydroxy compounds can be puri?ed cyclohexylcyclopentadienyl) ruthenium, bis( 1-hydroxy-3 by sublimation and are quite reactive materials, particu benzylcyclopentadienyl)nickel, bis(l - hydroxy-S-p-tolyl larly to oxygen, and are preferably handled therefore in cyclopentadienyl)cobalt(lII) reineckate cyclopentadi~ 70 the absence of oxygen and conveniently under an atmos phere of nitrogen or under high vacuum techniques. enyl(1 - hydroxy - 3~methylcyclopentadienyl)iron, cyclo The preferred puri?caton method for the free hydroxy pentadienyl(1 - hydroxy - 3,4 - diphenylcyclopentadi compounds is by sublimation onto a cold surface at ele e n y l)i r o n, (l - hydroxy - 3 - methylcyclopentadienyl) vated temperatures under greatly reduced pressures. (phenylcyclopentadienyl)cobaltQIII) tetrabromoferrate, 75 Generally speaking, such sublimation puri?cation is car 2,849,470 7 8 riledv out in the range 50-450.", C.,..using conveniently a molar proportions ofcyclopentadiene, followed by the wateneooled condensation ‘surface, and operating at pres addition of 2.5 molar proportions of ferrous chloride, sures inthe range of 0.1; to 1.0 mm. of mercury. all operations being conducted in liquid ammonia. The ‘As illustrated in the foregoing examples, the hydroxy ammonia is allowed to evaporate, deoxygenated water substituted dicyclopentadienyl group VI-VIII metal com added, and the resulting mixture ?ltered. The insoluble pounds of the present invention are conveniently prepared fraction contains some dicyclopentadienyl iron, and the through the reaction under anhydrous oxygen-free con aqueous ?ltrate is reacted with benzoyl ‘chloride to yield ditions of two molar proportions of an alkali metal amide a mixture of bis(1~benzoyloxy-3-methylcyclopentadienyl) in liquid ammonia and a cyclopentenone carrying at least iron and (cyclopentadienyl) (1-benzoyloxy-3-methylcyclo two hydrogens on annular carbon followed by metathesis 10 pentadienyl?ron. Fractional crystallization from metha With a salt of the desired transition metal of groups nol yields the desired (cyclopentadienyl)(l-benzoyloxy VI—VIII. The alkali metal amide can be that of any of 3~methylcyclopentadienyl)iron. the alkali metals, e. g., lithium, sodium, potassium, and The new hydroxydicyclopentadienyl group VI-VIII the like, but for obvious reasons of availability and costs metal compounds of this invention, including the nuclear the sodium and potassium amides are preferred. The 15 hydrocarbon-substituted hydroxydicyclopentadienyl group cyclopentenones can have no more than one substituent VI—VIII metal compounds, no matter what preparative on. each annular carbon and must have at least two hy means are used, are generally isolated from the reaction drogens on annular carbon, at least one of which is on mixture and puri?ed in the form of their salts, through annular carbon immediately adjacent to the annular either the metal or the hydroxyl, generally the former, or carbon carrying the oxo oxygen, with the said adjacent ethers or esters through the hydroxyl group or groups hydrogen-bearing > carbon carrying only single bonds. and particularly the esters of the monoba-sic carboxylic Thus, since there is one double bond internal to the ring acids. These organic acid esters are conveniently formed structure and one externally bonded oxo oxygen the under conventional Schotten-Baumann conditions by valence requirements permit no more than four sub simply adding an excess of the required carboxylic acid stituents on the cyclopentenone ring. Thus, the cyclo 25 halide under alkaline conditions to the ?ltrate from the pentenones which can be used as intermediates in prepar water-quenched reaction mixture after all insoluble by ing the new compounds of this invention are described by products have been removed, i. e., to a solution of the the following two structural formulas which vary only alkali or alkaline earth metal salt through the hydroxyl in the position of the necessary intra-ring unsaturation. group of the hydroxymetallocene. The ethers may be 30 obtained from the solution of the alkali metal salt of the —'n hydroxy compound by reaction with alkylating agents, particularly dimethyl sulfate. The organic acid ester separates as a solid which is removed by ?ltration and further puri?ed by conventional recrystallization pro ll) 35 cedures. Suitable unreactive liquid organic‘ solvents commonly used in recrystallization of organic compounds wherein the R’s can be alike or different, and are used’ are likewiseu-seful here, e. g., the aliphatic and aromatic as before to represent hydrogen or monovalent solely hydrocarbons, such as benzene, the xylenes, n-hexane, and hydrocarbon radicals, e. g., as indicated in the above the like; halogenated aliphatic and aromatic hydrocar speci?cally enumerated examples of the ?nal products, 40 bons, e. g., chloroform, the chlorobenzenes, and the like; such as alkyl, aryl, .cycloalkyl, aralkyl, or alkaryl radi the hydrocarbon ethers, e. g., diethyl ether, di-n-butyl cals, each usually of no more than seven carbons, and ether, and the like; or the substantially anhydrous organic preferably free from aliphatic unsaturation and most acids, such as glacial acetic acid, and the like. preferably of no more than four carbons apiece. It is Like other of the peculiar dicyclopentadienylmetal also preferred that no more than two aryl groups be on compounds recently reported in the literature, as men adjacent ring carbons. From the foregoing, it is appar tioned in the foregoing, these new oxy-substituted dicyclo ent also that the mononuclearly unsaturated carbocyclic pentadienyl group VI-VIII metal compounds have two ketone, i. e., the cyclopentenones, can have the carbons cyclopentadiene radicals directly linked through carbon of the S-membered carbonyl-containing rings as members thereof to the respective ‘metal atom. Furthermore, the of that ring alone, i. e.,’ the cyclopentenone ring carbons two cyclopentadiene nuclei are each singly bonded to the are annular members of no other ring. - said metal and yet all the carbons of each cyclopentadiene Additional illustration of the new hydroxydicyclopen ring'are identically bonded, i. e., the formal valence bond tadienyl groups VI-VIII metal derivatives of the present of each ring to the metal atom is not centered in any one invention is afforded by the reaction in liquid ammonia of the ?ve-ring carbons but equally in all. The struc of 3-methyl-2-cyclopenten-l-one with two molar propor 55 ture of the over-all molecule is similar to that of a sand tions, based on the ketone, of lithium amide, followed wich wherein the planes of the two cyclopentadiene rings byv reaction with anhydrous manganous chloride in 0.5 are essentially parallel, with the metal atom equidistant molar proportion, based on the ketone, resulting in the therebetween. Many recent references in the literature formation of bis(1-hydroxy-3-methylcyclopentadienyl) reporting on ultraviolet7 X-ray, and infrared properties manganese, conveniently isolated and characterized in the and other fundamentalphysical studies capable of de form of its stable dialkyl ethers, e. g., the, dimethyl ether, ?ning the molecular geometry of these compounds attest by reacting the aqueous sodium hydroxide solution with, to the foregoing peculiar'structure for other dicyclo'penta for example, dimethyl ‘sulfate. dienyl metal compounds. See, for‘instance, Wilkinson Similarly the reaction of 3-methyl-2-cyclopenten-l-one et al., I. Am. Chem. Soc. 74, 2125 (1952), Woodward in liquid ammonia with two molar proportions of potas 65 et al., ibid., 3458; Eiland et al., ibid., 4971; Fischer et al., sium amide, based on the ketone, followed by reaction Z. f. Naturforschung, 7B, 377 (1952); and Dunitz et al., with anhydrous hexaamminochromium(III) nitrate in 0.5 ~Nature, 171, 121 (1953). molar concentration, based on the ketone, results in a The new hydroxydicyclopentadienyl group VI~VIII product, which on warming with dilute alkali and fol metal compounds of this invention, including the nuclear lowed by acidi?cation yields bis(1-hydroxy-3-methylcyclo 70 hydrocarbon substituted hydroxydicyclopentadienyl metal pentadienyDChromium. . compounds are colored‘, reactive solids, exhibiting infrared The preparation of (cyclopentadienyl)(1-hydroxy-3 spectra containing a strong absorption band at 3.25,u., methylcyclopentadienyl)iron can. be achieved by the reac which is characteristic for unsaturated C—H linkages as tion of 6 molar proportions of sodium amide with one well as. strong bands at 3.0g, 3.7g, and 3.9M, which are molar proportion of. 3-m_ethyl<2;cyclopenten-Lone and v 4 75 characteristic for, the hydroxyl- group andquite similar. 2,849,470 ‘ l0 to those of phenol. The spectra also exhibit sharp bands droxyl radical and one alkyl radical ofnot more than four‘ at the longer wave lengths. The esters of these hydroxy carbon atoms. compounds are in general colored, crystalline solids, solu 4. A compound of iron wherein the iron atom is di ble in a Wide range of organic solvents and characterized rectly bonded to two cyclopentadienyl nuclei, each of by ready handleability and good stability, making them which nuclei has directly, singly, and separately attached ideal intermediates for the preparation of other new and to different nuclear carbons thereof, as the sole substitu interesting dicyclopentadienyl group VI-VII metal com ents on said nuclei other than said iron atom, one hy pounds. The esters exhibit infrared spectra containing droxyl radical and one monovalent hydrocarbon radical, characteristic strong absorption bands at 3.25M and 5.76;», free from aliphatic unsaturation, and of not more than which are characteristic, respectively, for unsaturated C-H seven carbon atoms. linkages and ester-type carbonyl. The spectra also ex 5. A compound of iron wherein the iron atom is di hibit strong absorption bands at the longer wave lengths. rectly bonded to two cyclopentadienyl nuclei, each of The infrared spectra of the hydroxy and ester compounds which nuclei has directly, singly and separately attached are consistent with a sandwich-type structure, particularly to different nuclear carbons thereof, as the sole substitu in not exhibiting several of the bands characteristic for 15 ents on said nuclei other than said iron atom, at least the simple sandwich compounds such as dicyclopenta one and not more than two hydroxyl radicals per each dienyliron itself. As pointed out by Pauson, J. Am. of said nuclei, and at least one and not more than two Chem. Soc. 76, 2187 (1954), the intermediate infrared monovalent hydrocarbon radicals per each of said nuclei, absorption bands characteristic for the simple unsub said hydrocarbon radicals being free from aliphatic un stituted sandwich compounds disappear when both cyclo 20 saturation, and each of not more than seven carbon pentadiene rings are substituted, with more bands disap atoms. pearing as substitution increases. 6. A compound of iron wherein the iron atom is di The hydroxy compounds and their esters, ethers and rectly bonded to two cyclopentadienyl nuclei, each of salts are useful as pesticides and as anti-knock agents in which nuclei has directly, singly, and separately attached spark-ignition motor fuels, dye intermediates, etc., in 25 to different nuclear carbons thereof at least one and not which latter uses the hydroxy substituents are of particu more than two hydroxyl radicals per each of said nuclei, lar signi?cance in increasing appreciably the chemical the remaining valences of the nuclear carbons of each reactivity of the compounds over corresponding com cyclopentadienyl nuclei being satis?ed, other than by hy pounds not containing the oxy substituent. drogen, solely and separately with a total of not more than They are effective as plant nutrients in overcoming or 30 two monovalent hydrocarbon radicals per each of said nu combating iron de?ciency, i. e., agents for prevention of clei, said hydrocarbon radicals being free from aliphatic iron chlorosis, which is a current problem, particularly unsaturation, and each of not more than seven carbon in citrus culture. The esters and simple salts through atoms. the hydroxyl group are especially useful in this respect 7. A compound of iron wherein the iron atom is di being applied directly to the plant in aqueous solution 35 rectly bonded to two cyclopentadienyl nuclei, at least one at concentrations as low as 0.055 part per 800 parts of of which nuclei has directly attached to a nuclear carbon water. thereof a hydroxyl radical, each of said cyclopentadienyl As illustrated in the examples, these new compounds nuclei having a total of not more than two hydroxyl or their salt, ether, or ester derivatives are useful as pho radicals separately attached to diiferent nuclear carbons tographic developers. The oxycyclopentadienyl metal 40 thereof, the remaining valences of the nuclear carbons of compounds, especially the free hydroxy compounds, are each cyclopentadienyl nuclei being satis?ed, other than also of utility in the formation of new condensation poly by hydrogen, solely and separately with a total of not mers of the phenol formaldehyde type, i. e., they may more than two monovalent hydrocarbon radicals per be reacted with formaldehyde or a formaldehyde gen each of said nuclei, said hydrocarbon radicals being free erating derivative at temperatures varying from room tem 45 from aliphatic unsaturation, and each of not more than perature to about 100° C., preferably in the presence of seven carbon atoms. catalytic amounts of strong mineral acids to form poly 8. A compound of a transition metal from the ?rst meric products ranging from low melting thermosettable long series of group VIII of the periodic table wherein resins to infusible, insoluble products varying with the said transition metal is directly bonded to two cyclopenta temperature and time of reaction, and the relative con dienyl nuclei, at least one of which nuclei has directly centrations of formaldehyde and the acid catalyst. These attached to a nuclear carbon thereof a hydroxyl radical, polymeric products are believed to have a plurality of each of said cyclopentadienyl nuclei having a total of the oxymetallocene structures linked together through not more than two hydroxyl radicals separately attached methylene or polymethyleue bridges. to different nuclear carbons thereof, the remaining val The periodic table of the speci?cation and claims is the 55 ences of the nuclear carbons of each cyclopentadienyl usual one as given, for example, in Deming-General nuclei being satis?ed, other than by hydrogen, solely and Chemistry 5th edition, Wiley, 1944). separately with a total of not more than two monovalent The foregoing detailed description has been given for hydrocarbon radicals per each of said nuclei, said hydro- clearness of understanding only and no unnecessary lim carbon radicals being free from aliphatic unsaturation, itations are to be understood therefrom. The invention 60 and each of not more than seven carbon atoms. is not limited to the exact details shown and described 9. A compound of a transition metal from group VIII for obvious modi?cations will occur to those skilled in of the periodic table wherein said transition metal is the art. directly bonded to two cyclopentadienyl nuclei, at least The embodiments of the invention in which an exclusive one of which nuclei has directly attached to a nuclear property or privilege is claimed are de?ned as follows. 65 carbon thereof a hydroxyl radical, each of said cyclo I claim: pentadienyl nuclei having a total of not more than two 1. Bis ( lhydroxy-3-methylcyclopentadienyl)iron. hydroxyl radicals separately attached to different nuclear 2. The dibenzoate of bis(l-hydroxy-3-methylcyclopen carbons thereof, the remaining valences of the nuclear tao'ienyl)iron. carbons of each cyclopentadienyl nuclei being satis?ed, 70 other than by hydrogen, solely and separately with a 3. A compound of iron wherein the iron atom is di total of not more than two monovalent hydrocarbon rectly bonded to two cyclopentadienyl nuclei, each of radicals per each of said nuclei, said hydrocarbon radicals which nuclei has directly, singly, and separately attached being free from aliphatic unsaturation, and each of not to different nuclear carbons thereof, as the sole substitu more than seven carbon atoms. cuts on said nuclei other than said iron atom, one hy- ‘[5 10. A compound of a transition metal from groups VI 2,849,470 1 I 12 to VIII of the periodic table wherein said transition metal product an’ oxy-stibstituted dicyclopentadienyl compoundv .is directly bonded to two cyclopentadienyl nuclei, at least of a transition metal from groups VI to VIII of the’ one of which nuclei has directly attached to a nuclear periodic table“ ' carbon thereof a hydroxyl radical, each of said cyclo 17.’ Process which comprises bringing into contact and pentadienyl nuclei having a total of not more than two reacting in anhydrous liquid ammonia an alkali metal hydroxyl radicals separately attached to different nuclear amide with a .cyclopentenone having as the sole sub carbons thereof, the remaining valences of the nuclear stituents, other than carbonyl oxygen, at most two mono carbons of each cyclopentadienyl nuclei being satis?ed, valent hydrocarbon radicals free from aliphatic unsatura-_ other than by hydrogen, solely and separately with a tion and each of not more than seven carbon atoms, each total of not more than two monovalent hydrocarbon of said monovalent hydrocarbon radicals being attached radicals per each of said nuclei, said hydrocarbon radicals to separate annular carbons of said cyclopentenone, and being free from aliphatic unstaturation, and each of not thereafterreacting the resulting dialkali metallated prod more than seven carbon atoms. uct with a salt of atransition metal from group VIII of 11. A compound of a transition metal from groups the periodic table, and obtaining as the resulting product VI to VIII of the periodic table wherein said transition 15 an oxy-substituted dicyclopentadienyl compound of a tran-' metal is directly bonded to two cyclopentadienyl nuclei sition metal from group VIII of the periodic table. at least one of which nuclei has directly attached to a 18. Process which comprises bringing into contact and nuclear carbon thereof an oxy-oxygen, each of said cyclo reacting in anhydrous liquid ammonia an alkali metal pentadienyl nuclei having a total of not more than two amide with a cyclopentenone having as the sole sub oxy-oxygens separately attached to different nuclear car stituents, other than carbonyl oxygen, at’ most two mono bons thereof with each oxy-oxygen being directly and valent hydrocarbon radicals free from aliphatic unsatura singly attached to a member selected from the class con tion and each of not more than seven carbon atoms, each sisting of hydrogen, monovalent hydrocarbon radicals of said monovalent hydrocarbon radicals being attached free from aliphatic unsaturation and each of not more to separate annular carbons of said cyclopentenone, and than seven carbon atoms, carbacyl radicals free from ali 25 thereafter reacting the-resulting dialkali metallated prod phatic unsaturation and each of not more than seven uct with a salt of a transition metal from the ?rst long carbon atoms, ‘and alkali metals, the remaining valences series of group VIII of the periodic table, and obtaining of the nuclear carbons of each cyclopentadienyl nuclei as the resulting product an oxy-substituted dicyclopenta~ being satis?ed, other than by hydrogen, solely and sepa dienyl compound of a transition metal from the ?rst long rately with a total of not more than two monovalent hydro 30 series of group VIII of the periodic table. 7 carbon radicals per each of said nuclei, said hydrocar 19. Process which comprises bringing into contact and bon radicals being free from aliphatic unsaturation, and reacting in anhydrous liquid ammonia an alkali metal each of not more than seven carbon atoms. amide with a cyclopentenone having as the sole vsub 12. A compound of iron wherein the iron atom is stituents, other than carbonyl oxygen, at most two mono directly bonded to two cyclopentadienyl nuclei, each of 35 valent hydrocarbon radicals free from aliphatic unsatura which nuclei has directly, singly, and separately attached tion and each of‘not more than seven carbon atoms, each to different nuclear carbons thereof, as the sole sub of said monovalent hydrocarbon radicals being attached stituents on said nuclei other than said iron atom, one to separate annular carbons of‘ said cyclopentenone, and alkyl radical of not more than four carbon atoms and thereafter reacting the resulting dialkali metallated prod one carbacyloxy radical, free from aliphatic unsaturation uct with a salt of iron, and obtaining as the resulting prod and of not more than seven carbon atoms. uct an ~oxy~substituted dicyclopentadienyliron compound. 13. A compound of iron wherein the iron atom is 20. Process which comprises bringing into contact and ‘ directly bonded to two cyclopentadienyl nuclei, at least reacting in anhydrous liquid ammonia an alkali metal one of which nuclei has directly attached to a nuclear amide with a cyclopentenone having as the sole sub carbon thereof a carbacyloxy radical, free from aliphatic stituent, other than ‘carbonyl oxygen, one monovalent unsaturation and of not more than seven carbon atoms, hydrocarbon radical free from aliphatic unsaturation and each of said cyclopentadienyl nuclei having a total of not of no more than seven carbon atoms, and thereafter re more than two carbacyloxy radicals separately attached acting the resulting dialkali metallated product with a salt _ to. different nuclear carbons thereof, the remaining va of iron, and obtaining. as the resulting product an oxy lences of the nuclear carbons of each cyclopentadienyl 50 substituted dicyclopentadienyliron compound. nuclei being satis?ed, other than by hydrogen, solely and 21. Process which comprises bringing into contact and separately with a total of not more than two monovalent reacting in anhydrous liquid ammonia an alkali metal hydrocarbon radicals per each of said nuclei, said hydro amide with a cyclopentenone having as the sole sub carbon radicals being free from aliphatic unsaturation, stituents, other than carbonyl oxygen, an alkyl radical and each of not more than seven carbon atoms. of no more than four carbon atoms, and thereafter react 14. An ester of bis(1-hydroxy-3-methylcyclopentadi ing the resulting dialkali metallated product with a ferrous enyl)iron with a hydrocarbon carboxylic acid, free from halide, and obtaining as the resulting product an oxy aliphatic unsaturation, and of not more than seven carbon substituted dicyclopentadienyliron compound. atoms. 22. Process which comprises bringing into contact and 15. An ester of a bis(1-hydroxy-3-methylcyclopentadi reacting in anhydrous liquid ammonia sodium amide with enyl)metal, wherein the metal is from the ?rst long series 3-methyl-2-cyclopenten-l-one, and thereafter reacting the of group VIII of the periodic table, with a hydrocarbon resulting disodium metallated product with ferrous chlo carboxylic acid, free from aliphatic unsaturation, and of ride, and obtaining as the resulting product bis(l-hy not more than seven carbon atoms. ‘ droxy-3-methylcyclopentadienyl) iron. 16. Process which comprises bringing into contact and 23. Process which comprises bringing into contact and reacting in anhydrous liquid ammonia an alkali metal reacting in anhydrous liquid ammonia an alkali metal amide with a cyclopentenone having as the sole sub~ amide with .a cyclopentenone having as the sole sub stituents, other than carbonyl oxygen, at most two mono stituents, other than carbonyl oxygen, at most two mono valent hydrocarbon radicals free from aliphatic unsatura valent hydrocarbon radicals free from aliphatic unsatura tion and each of not more than seven carbon atoms, each tion and each of not more than seven carbon atoms, each of said monovalent hydrocarbon radicals being attached of said monovalent hydrocarbon radicals being attached to separate annular carbons of said cyclopentenone, and to separate annular carbons of said cyclopentenone, and thereafter reacting the resulting dialkali metallated prod thereby' obtaining a dialkali metallated cy-clopentenone. uct with a salt of a transition metal from groups VI to 24; Process which comprises bringinginto contactand VII-Ii'of¢.‘the/per~iodic table,=>and obtaining as the-resulting 75 ‘reacting'in ‘anhydrous liquid ammonia an alkali metal " 2,849,470 '13 amide with a cyclopentenone having as the sole sub OTHER REFERENCES stituent, other than carbonyl oxygen, an alkyl radical of Woodward et a1.: Jour. Amer. Chem. 800., vol. 74, no more than four carbon atoms, and thereby obtaining pp. 3458-59, July 1952. a dialkali metallated alkylcyclopentenone. Paulson: Jour. Amer. Chem. Soc., vol. 76, pp. 2187 25. Process which comprises bringing into contact and 5 2191, April 20,- 1954. reacting in anhydrous liquid ammonia sodium amide with Rosenblum: The Structure and Chemistry of Ferro 3-methy1-2-cyc1openten-l-one, and thereby obtaining the cene, A Thesis Presented to the Dept. of Chem., Harvard disodium metallated 3-methy1-2-cyc1openten-l-one. Univ., Cambridge, Mass, August 1953; deposited in the Harvard Univ. Lib‘. February 19, 1954; page 37. References Cited in the tile of this patent 10 UNITED STATES PATENTS 2,683,157 Weirmayr ______.._ July 6, 1954 UNITED STATES PATENT OFFICE Certi?cate of Correction August 26, 1958 V Patent No. 2,8li9,4=70 Richard Edward Benson It is hereby certi?ed that error appears in the printed speci?cation of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below. Column 3, lines 80 to 42, in the table, heading to second column thereof, for “Development” read ——Development Time——; column 7, lines 30 to 36, the left-hand portion of the formula should appear as shown below instead of as in the patent

Signed and sealed this 18th day of November 1958.

[SEAL]

Attest: ROBERT C. WATSON, KARL H. AXLINE, Gommz'asioner of Patents. Attesti'ng Oy?cer. UNITED STATES PATENT OFFICE Certi?cate of Correction August 26, 1953“ i’ Patent No. 2,849,470 Richard Edward Benson or appears in the printed speci?cation of the above It is hereby certi?ed that err tters Patent should read numbered patent requiring correc t1on and that the said Le as corrected below. to second column thereof, for Column 3, lines 30 to 4:2, in the table, heading es 30 to 36, the left~hand “Development” read ——Development Time—; column 7, lin d of as in the patent portion of the formula should appear as shown below instea

ll 0 Signed and sealed this 18th day of November 1958.

[SEAL]

Attest = ROBERT C. WATSON, "M" KARL _H. AXLINE, Commissioner of Patents. Attesting Oy?cer.