3,361,779 United States Patent Office Paterated Jan. 2, 1968 1. 2 bon of the aromatic ring is bonded apparently by co 3,361,779 ORGANOMETALLC COMPOUNDS ordinate covalence in a fashion such that the ring con Thomas H. Coffield, Heidelberg, Germany, and Rex D. tributes six electrons to the metal atom. Likewise, the Closson, Northville, Mich., assignors to Ethyl Corpo other electron donor groups also are covalently or co ration, New York, N.Y., a corporation of Virginia 5 ordinatively bonded to the metal atom. Such donation of No Drawing. Filed Aug. 20, 1959, Ser. No. 834,931 electrons contributes materially to the stability of the 18 Claims. (Cl. 260-429) molecule since the metal atoms, with the donated elec trons, approaches the electron configuration of the next This application is a continuation-in-part of my earlier higher rare gas. In a preferred embodiment of this inven filed copending application, U.S. Ser. No. 690,909, filed on () tion the compound has the electron configuration of the Oct. 18, 1957, now abandoned. next higher rare gas. For example, the chromium atom in This invention relates to novel organometallic com benzene chromium tricarbonyl has the electron configura pounds and their preparation. More particularly the pres tion of krypton. Thus, in the case of benzene chromium ent invention relates to novel and useful aromatic transi tricarbonyl, the three CO groups donate a total of six tion metal complexes. electrons and the benzene molecule donates six electrons, An object of this invention is to provide a novel class giving a stable compound which can be illustrated as foll of organometallic compounds. Another object is to pro lows: wide a novel class of stable aromatic transition metal co ordination compounds. A further object is to prove a novel class of stable non-ionic aromatic metal complexes having unsymmetric configurations. A still further object is to pro vide a class of stable non-ionic aromatic transition metal The novel aromatic metal compounds of this invention complexes in which a single aromatic molecule is coordi find a number of uses. In particular, the compounds are nated with a metal atom. Other objects will become ap valuable as polymerization catalysts in the polymeriza parent from the following discussions. 25 tion of unsaturated hydrocarbons wherein they have the The above objects are accomplished by a non-ionic com advantage of supplying the aromatic molecule which is plex aromatic metal compound of the metals of Groups sometimes necessary to promote polymerization and in ad IV-B through VI-B having a single aromatic molecule dition are soluble both in the hydrocarbon itself, the sol bonded to the metal through the carbon atoms of the ben vent medium, and the resulting polymers. Further, the Zene ring, which compound is stabilized by additional co 30 compounds of this invention are useful as dryers in organic valent bonding to dissimilar electron-donating groups. The drying oil compositions and as metal sources in gas-phase metal in the novel compounds of this invention is a metal plating. of Groups IV-B, V-B and VI-B of the Periodic Table as The aromatic compounds coordinated to the metal in shown in the Handbook of Chemistry and Physics (37th the compounds of this invention, which are represented by edition; the Chemical Rubber Publishing Co., Cleveland, 35 A in the above formula, are, in general, compounds con Ohio, 1955) on pages 392 and 393, and thus includes those taining an isolated benzene nucleus. That is, aromatic metallic elements having atomic numbers of from 22 compounds which are free of aliphatic unsaturation on a through 24, 40 through 42 and 72 through 74. carbon atom adjacent the benzene ring and which do not The compounds of this invention may be represented by contain unsaturation on a carbon atom of a fused ring the formula 40 which carbon atom is adjacent the benzene nucleus. The AMQ aromatic compounds applicable to the compounds of this wherein A represents an aromatic compound having a invention have no aliphatic double bond in conjugated benzene nucleus coordinted to the metal atom, M, through relationship to the ring. Thus, aryl and alkyl substituted the carbon atoms of the benzene ring and Q represents aromatic compounds are applicable to this invention, as discrete combinations of non-aromatic electron donor are fused ring compounds having isolated benzene nuclei, groups involved in covalent or coordinate-covalent bond that is, having no unsaturation on a carbon atom adjacent ing with the metal atom. to the benzene ring. Aromatic compounds having from 6 These novel compounds achieve stabilization through to 18 carbon atoms are generally preferred in compounds coordination of sufficient electrons to give the metal atom of this invention. Benzene itself, mesitylene, toluene, bi the electronic configuration similar to that of the next 50 phenyl, Tetralin, m-hexyl-biphenyl and the like are ex higher rare gas. The compounds of this invention can also amples of applicable aromatic compounds. be represented by the formula In some cases, other aromatic compounds which do not have an isolated nucleus are desirable. Typical examples AM (B)(C) of such compounds are styrene cyclopentadienyl chloro wherein A and Mare defined above and B and C represent 55 chromium, methyl-styrene cyano vanadium tricarbonyl, electron-donating entities capable of donating form 1 to 8 naphthalene dichloro titanium dinitrosyl, anthracene di electrons to the metal atom, b is an integer ranging from ethylmolybdenum dimethylene diamine, 1-ethyl naphthal 1-8, and c is an integer ranging from 0-4, such that the ene amylvanadium tricarbonyl, and the like. atomic number of the metal M, plus b times the number The metal constituent in the compounds of the present of electrons donated by b, plus c times the number of elec 60 invention are transition metal elements of the fourth, fifth trons donated by C plus the six electrons donated by the and sixth periods of the Periodic Table. These elements aromatic molecule A equals an integer having a value of constitute Groups IV-B, V-B and VI-B of the Periodic from two less than the atomic number of the next higher Table and include, in group IV-B, titanium, zirconium rare gas to the value of the next higher rare gas. and hafnium; in Group V-B, vanadium, niobium, and The compounds of this invention are quite different tantalum; and in Group VI-B, chromium, molybdenum from any compound heretofore known. The aromatic por and tungsten. tion of the compound is actually a molecule, as distin The constituents represented by B and C in the above guished from an aryl radical, e.g., phenyl, which is found formula are electron-donating groups capable of coordi in organometallic compounds. The aromatic molecule is 70 nating with the metal atom in the novel compounds of not bonded to the metal through a single carbon atom, as this invention, and donating thereto from 1 to 8 electrons. in the usual aryl metal compounds but, instead, each car That is, the groups represented by B and C in the above 3,361,779 3 4. formula are capable of sharing electrons with the metal amine, benzene vanadium nitrosyl butadiene, amyl atom so that the metal achieves a more stable structure benzene chromium cyclohexadiene carbonyl, toluene tri by virtue of such added electrons. A preferred embodi methyl hafnium N,N'-diphenylmethylenediamine, toluene ment of this invention comprises those compounds in dicyano zirconium cyclohexadiene and the like. which the metal has attained the electron configuration A preferred cyclic diolefin donor used in forming the of the next higher rare gas by virtue of the coordinating compounds of our invention is cyclopentadiene. Com groups, as it is found that these compounds have excep pounds in which an aromatic molecule, as defined above, tional stability. and a cyclopentadiene molecule are both coordinated with These electron-donating groups in coordination with a metal atom of Groups IVB-VIIB, are stable and have the metal are, generally, either organic radicals or O the characteristics of volatility and fuel solubility which molecular species which contain labile electrons, which make them more valuable as gasoline additives than electrons assume more stable configuration in the molecule certain of the other compounds of our invention. The when associated with the metal. The electron-donating cyclopentadiene molecule may contain from 5 to about groups applicable to the compounds of this invention may 13 carbon atoms and may be substituted with various also be inorganic entities which are capable of existing groups such as alkyl, aryl, cycloalkyl, halogen nitro groups as ions, such as hydrogen, the cyanide group, and the and the like. Typical of such compounds are mesitylene various halogens. titanium cyclopentadiene dicarbonyl, toluene zirconium Donors capable of sharing a single electron with a methylcyclopentadiene dicarbonyl, hexamethylbenzene metal atom include monovalent organic radicals, the hy niobium cyclopentadiene nitrosyl, chlorobenzene vana drogen atom, the cyanide group CN, and the halogens, 20 dium trichloromethylcyclopentadiene carbonyl hydride, fluorine, chlorine, bromine and iodine. These groups Xylene dichloro chromium nitrocyclopentadiene, N,N- function as electron donors by sharing an electron with diethylaniline molybdenum cyclopentadiene carbonyl and an electron of the metal atom in a single covalent bond. anisole chromium benzylcyclopentadiene triphenylphos Examples of the aromatic metal coordination compounds phine. of this invention containing such a donor group include 25 The cyclopentadienyl radical contributes five electrons toluene heptabutyl zirconium, mesitylene tetracyano tri to certain of the novel aromatic metal coordination com chloro vandium, ethylbenzene tribromo trihydro molyb pounds of this invention. The cyclopentadienyl radical denum, benzene hexaethyl chromium, isopropyl benzene found in these novel compounds contain from 5 to about heptabromo tantalum, benzene octachloro titanium and 13 carbon atoms and thus includes the substituted cyclo the like. 30 pentadienyl hydrocarbon radicals having up to 8 carbon When the electron donor group bonded to the metal atoms in a side chain substituent which may be bonded atom in a compound of this invention is, or contains, a to more than one ring carbon atom. Examples of such 'monovalent organic radical, this organic radical prefer radicals include the octylcyclopentadienyl radical, the ably contains up to 13 carbon atoms. These preferred methylcyclopentadienyl radical, the idenyl radical and Organic radicals include alkyl, aryl, alkaryl, araikyi, 35 the like. Examples of the novel aromatic coordination alkenyl radicals and the like. Specific examples include compounds of this invention containing such a cyclopenta radicals derived from the following hydrocarbons: dienyl radical include benzene cyclopentadienyl chromi methane, ethane, propane, n-octane, 4-aryloctane, 2 um, toluene cyclopentadienyl methyl molybdenum, mesi phenyl heptane and the like. tylene octylcyclopentadienyl niobium carbonyl, ethyl Entities capable of sharing two electrons with a metal 40 benzene methylcyclopentadienyl hafnium nitrosyl and the atom in the aromatic metal coordination compounds of like. this invention include monoolefins, ammonia, primary Aliphatic trienes represent entities capable of contribut Secondary-, and tertiary amines, cyclic nitrogen com ing six electrons to the metal in the aromatic metal co pounds wherein the nitrogen is in the trivalent state, ordination compounds of this invention. For this purpose organo phosphine compounds, phosphine halides, arsines, comopunds containing the three double bonds in conju stibines, bismuthines; mixed hydroorganic phosphines, gated relationship are preferred. Toluene tungsten hexa stibines, arsines and bismuthines, isonitrile and the like. triene, benzene chloro vanadium 3-methylhexatriene and Examples of the aromatic metal coordination compounds benzene titanium nitrosyl 2,2-dimethylhexatriene carbon of this invention which contain such donating groups in y are examples of aromatic metal coordination com clude benzene zirconium tetra-(methyl isonitrile), pounds Stabilized by a conjugated triene electron donor mesitylene chlorovanadium tricarbonyl, benzene tung group. sten-tris-phosphorus trichloride, toluene dimethylmolyb The novel aromatic metal coordination compounds of denum diammonia, benzene niobium-tris-diphenyl amine this invention may contain a cycloheptatrienyl radical and the like. which contributes seven electrons in coordinate covalent The nitrosyl group, NO, is an example of an entity 55 bonding to the metal. The cycloheptatrienyl radical may capable of donating three electrons to a metal atom in the be substituted with other hydrocarbon group and may novel aromatic metal coordination compounds of this contain a total of up to 15. carbon atoms. Examples of invention. Examples of these novel compounds which con the aromatic metal coordination compounds of this inven tain the nitrosyl coordination group include benzene tion which contain such cycloheptatrienyl radicals include molybdenum dinitrosyl, amylbenzene chromium carbonyl benzene cycloheptatrienyl vanadium, toluene methylcy nitroSyl, isopropylbenzene dibromovanadium nitrosyl, 60 cloheptatrienyl zirconium, mesitylene ethylcyclohepta benzene titanium dinitrosy and the like. trienyl chlorotitanium, benzene octyl cycloheptatrienyl In the novel aromatic coordination compounds of this methylzirconium and the like. invention certain groups are capable of sharing four Tetraenes and in particular cyclooctatetraene may be electrons in coordinate covalent bonds with the metal present in the aromatic metal coordination compounds atom. These four electron donor groups include organic of Group IVB. These tetraenes contribute 8 electrons in diamines, aliphatic diolefins, cyclic diolefins particularly coordinate covalent bond with the metal. Such aromatic those having conjugated double bonds, although non metal tetraene compounds are exemplified by benzene conjugated diolefins are also applicable. When the donor titanium cyclooctatetraene. group is a diamine best results are obtained when the The novel aromatic metal coordination compounds of methylene chain connecting the two nitrogen atoms is this invention are susceptible to preparation by several no longer than three carbons in length. Typical examples methods. One of these comprises the preparation of a of the aromatic metal coordination compounds of this diaromatic metal complex followed by subsequent replace invention which contain stabilizing groups donating four ment of an aromatic group with an electron donating electrons include mesitylene titanium bis-dimethylene di 75 entity or entities. This may be accomplished in a single 3,361,779 5 S step or through a plurality of steps which include the such as pentane, hexane, decane, and the like. These di preparation of an aromatic metal coordination compound luents can be used in concentrations of from 0.01 to 100 in which the aromatic-metal-ligand portion of the mole parts per part of the aromatic compound. cule exists as a cation followed by reduction of such ion Other Group VI-B metal compounds of this invention to the neutral coordination compound of this invention. are toluene chromium tricarbonyl; ethylbenzene chrom In other cases the reaction product derived from replacing ium dinitrosyl; toluene cyclopentadienyl cyanochromium; an aromatic group of a diaromatic metal complex is a mesitylene methylcyclopentadienyl bromochromium; allyl neutral coordination compound of this invention which is benzene indenyl methylmolybdenum; p-methyldiphenyl obtained without further reduction of the metal. In other octylcyclopentadienyl cyanochromium; triphenylmethane instances the novel compounds of this invention are con chromium N,N,N',N'-tetramethyl-methylenediamine car veniently prepared by introducing an aromatic molecule 10 bonyl; sec-butylbenzene trichlorochromium nitrosyl; eth in coordinate covalent bonding in a metal coordination ylbenzene chromium triammonia; hexamethylbenzene cy compound such a metal carbonyl derivative. The result clopentadienyl phenylmolybdenum; benzene pentachloro ing intermediate may be an ionic compound which can be cyanomolybdenum; toluene molybdenum tris-dodecyl converted into the neutral aromatic metal coordination 5 amine; benzene tungsten tris-phenyl isonitrile; o-xylene compound of this invention. Another method for the tungsten tris-tri-iodophosphine, and the like. preparation of the compounds of this invention consists of introducing into a metal compound an aromatic mole Example II cule by means of an appropriate reagent such as a phenyl Methylcyclopentadienyl bromochromium tricarbonyl Grignard and subsequently converting the resulting com 20 (300 parts), 850 parts of toluene and 180 parts of ferric plex to the neutral aromatic coordination compound de chloride are heated to reflux over a period of six hours sired. These methods will become further apparent by with constant agitation. During this heating an amount of reference to the following specific examples in which all gas is given off corresponding to the total amount of car parts and percentages are by weight unless otherwise bon monoxide in the carbon compound. After the reac stated. 25 tion vessel is cooled the contents are hydrolyzed with 80 Example I parts of weakly acidified water and the organic layer is To a glass reaction vessel equipped with stirring means, separated. Toluene methylcyclopentadienyl bromochro heating means and reflux condenser were added 35 parts mium is separated in good yield from the organic layer. of chromium hexacarbonyl, 23 parts of aluminum chlo The methylcyclopentadienyl bromochromium tricarbonyl ride as a catalyst and 430 parts of mesitylene, the excess 30 employed in this example is prepared by first treating chro as a carrier. The mixture was agitated and heated to re mium carbonyl with methylcyclopentadienyl sodium and flux for 3 hours during which time gas evolved and was then adding HgCl2. The resulting salt is bromonated to collected. The quantity of gas evolved corresponded to give the methylcyclopentadienyl bromochromium tricar three equivalents of carbon monoxide. After discontinua bonyl. tion of heating and reflux the reaction mixture was cooled Further examples of Group VI-B aromatic coordina and hydrolyzed with 300 parts of cold water and the or tion compounds of this invention include n-octylbenzene ganic layer containing mesitylene chromium tricarbonyl chromium ethylenediamine carbonyi; n-butyl-benzene was separated. To recover the mesitylene chromium tri molybdenum tricarbonyl; sec-butylbenzene tungsten tri carbonyl from this solution the mesitylene is evaporated ammonia; benzene molybdenum carbonyl trimethylene and the residue carefully sublimed. The mesitylene chrom 40 diamine; toluene pentamethyl chlorotungsten; Inesitylene ium tricarbonyl is insoluble in water but soluble in or pentacyano hydromolybdenum; benzene indenyl cyano ganic solvents and is oxidatively and thermally stable at tungsten; mesitylene tungsten tri-2,5-diaminohexane; oz temperatures in excess of its melting point which is above methylbutylbenzene dichlorochromium bis-triphenylphos about 110° C. phine; mesitylene chromium bis-butyl dibromophosphine; In this preparation the aluminum chloride compound toluene chlorochromium nitrosyl; mesitylene dicyano di is replaced by other Friedel-Crafts type catalyst. By a methylchromium; benzene tetramethyl chloromolyb Friedel–Crafts catalyst is meant a salt having electrophilic denum; p-xylene tetracyanotungsten carbonyl, etc. characteristics. These are usually halides of metals of Groups II-A, II-B, HI-A, IV-B, V-B, VI-B, VII-B and Example III VIII of the Periodic Table. The preferred halides are 50 Cyclopentadienyl chloromolybdenum tricarbonyl is re halides of Groups III-A, IV-B and Viii. illustrative ex acted with p-xylene in the presence of aluminum chloride amples of preferred metal halides are boron trifluoroide, to produce p-Xylene cyclopentadienyl chloromolybdenum. boron trichloride, boron tribromide, boron triiodide, all The starting material is prepared in a manner similar to minum tifluoride, titanium tetrachloride, titanium tetra that described in Example II for methylcyclopentadienyl bromide, ferric chloride, and the like. Also, in many in 5 5 bromochromium tricarbonyl. stances, it is desirable to employ the corresponding hydro Still other examples of Group VI-B compounds of this halide along with the metal halide e.g. a boron trichloride invention include benzene cyclopentadienyl chlorochro hydrogen chloride catalyst system. Other examples of mium, mesitylene methylcyclopentadienyl cyanochro suitable Friedel–Crafts catalysts of generally lesser activ mium; o-xylene ethylcyclopentadienyl hydrochromium; n ity are zinc, gallium, indium thallium, beryllium, magne 6) butylbenzene tri-n-hexyl chromium nitrosyl; cumene sium, zirconium, Vanadium, chronium, manganese and chromium dinitrosyl, isopropylbenzene chromium tris-di cobalt halides. propylamine; toluene tetramethylchromium tert-phenyl The Friedel-Crafts reaction is preferably carried out in amine; m-xylene pentacyano ethylchromium; prehnitene a liquid medium consisting primarily of the aromatic com diiodochromium propylenediamine; durene cyclopentadi pound which is reacted with the metal compound reactant. 65 enyl chromium; benzene chromium carbonyl nitrosyl; tol Thus, if it is desired to make the benzene chromium tri uene cyclopentadienyl chromium; mesitylene methylcyclo carbonyl, the reaction is conducted in a benzene medium. pentadienyl chromium; o-xylene ethylcyclopentadienyl The reaction can also be conducted in a halogenated ben chromium; ethylbenzene n-octylcyclopentadienyl molyb Zene such as chlorobenzene or bromobenzene, in which denum; diphenyl diethylcyclopentadienyl molybdenum; n event the chloroaromatic or bromoaromatic manganese butylbenzene indenyi tungsten; cumene chromium nitrosyl tricarbonyl halide is formed. Other substituted aromatic carbonyl; amylbenzene molybdenum nitrosyl ammonia; compounds can be produced in like manner. m-diphenylbenzene n-amyl chromium dicarbonyl; 1,2,3- In addition to the aromatic compound, other solvents triethylbenzene ethylcyclopentadienyl chromium; isopro or diluents can be employed. Typical examples of such pylbenzene cyanochromium bis-diisopropylamine and diluents are nitrobenzene: straight chain hydrocarbons 75 the like. 3,361,779 7 3. Example IV Example VII To a solution of one mole of soduim cyclopentadienide Working in a nitrogen atmosphere, 120 parts of tita (prepared from cyclopentadiene and sodium in tetrahy nium dichloride, 290 parts of aluminum tribromide and drofuran) was added dropwise under cooling 0.25 mole 1000 parts of ethylbenzene are refluxed for four hours. vanadium tetrachloride. The solution was blanketed with While the nitrogen atomsphere is maintained the reaction nitrogen. The reaction is very violent, due in part to the mixture is hydrolyzed with water and the organic layer complexing of the vanadium tetrachloride with THF. A containing di(ethylbenzene) titanium is then transferred dark reddish-purple solution resulted. This solution was while under nitrogen to a pressure resistant vessel. The charged to an autoclave and treated with carbon monox vessel is sealed and pressured with carbon monoxide to O ide at a temperature of 175° C. and a pressure of 3000 a pressure of about 500 p.s.i.g. and the temperature is p.s. i. CO for one hour. After cooling the reaction mixture elevated to about 165° C. These conditions are main was discharged, the solvent evaporated under nitrogen, tained for about three hours after which time the pres and the cylopentadienyl vanadium tetracarbonyl product sure is vented, the vessel is discharged and the contents was sublimed in high vacuum at 70-80 C. The sublimate subjected to fractional distillation at reduced pressure. 5 was obtained as golden orange crystals, volatile and hydro Ethylbenzene titanium tetracarbonyl having the formula carbon soluble, M.P. 138 C. Analysis of the product in CHCHTi(CO)4 results. dicated that it contained 22.3 percent vanadium which Representative Group IV-B compounds of this inven corresponds very well with the calculated analysis for tion include p-diphenylbenzene diisobutyl zirconium tri CHOV of 22.34 percent vanadium. This cyclopenta carbonyl: 1,3,5-triethylbenzene dibromo hafnium tri-tert 20 dienyl vanadium tetracarbonyl (1.0 mole) is treated with butylamine; 1-n-hexyl-3-isopropylbenzene dicyanotitanium 1.1 mole (a slight excess) of aluminum tribromide in the tris-sec-dodecylamine; benzene difluorozirconium tris presence of a tenfold excess of toluene. The mixture is tert-phenylamine; p-cymene pentamethyl tri-heptyl tita refluxed for about 2 hours, and after hydrolysis and frac nium; benzene tetracyano tetramethyl titanium; toluene tional distillation of the resulting organic layer, toluene pentaethyl zirconium nitrosyl; hexamethylbenzene dinon cyclopentadienyl vanadium carbonyl is isolated and puri yltitanium tricarbonyl; durene amylcyclopentadienyl tri fied by recrystallization at reduced temperatures. - amyltitanium; benzene methylcyclopentadienyl dichloro Examples of other Group V-B compounds of this in titanium; diphenyl titanium tris-tert-phenylamine; allyl vention include benzene methylcyclopentadienyl vanadium benzene titanium tris-triiodophosphine; n-amylbenzene carbonyl; toluene cyclopentadienyl dicyanovanadium; p ethyl titanium dinitrosyl; toluene chlorotitanium tricar 30 xylene butylcyclopentadienyl vanadium; ethylbenzene bonyl; benzene butylzirconium triammonia; benzene Zir pentahydro vanadium ammonia; mesitylene di-methylcy conium tricarbonyl; toluene hafnium dinitrosyl; benzene clopentadienyl dibromovanadium; cumene methylvana trimethyl hafnium nitrosy and the like. dium dinitrosyl; benzene ethylvanadium tricarbonyl; iso Example V propylbenzene iodo-vanadium dinitrosyl; allylbenzene Dicyclopentadienyl titanium dichloride is refluxed with 35 vanadium nitrosyl dicarbonyl; n-amylbenzene Vanadium mesitylene in the presence of aluminum chloride. The re nitrosyl ethylenediamine; sec-butylbenzene chloro niobium action mixture is maintained at reflux for up to 24 hours tricarbonyi; 2,3-dimethylbenzene indenyl vanadium car after which time mesitylene cyclopentadienyl dichloro bonyl; p-indenyltoluene methylcyclopentadienyl vanadium titanium is recovered. butylisonitrile; mesitylene vanadium 3,5-diaminodecane Other Group IV-B metal compounds of this invention 40 nitrosyl; 2-phenylpentane chlorovanadium dinitrosyl; p include benzene cyclopentadienyl titanium nitrosyl; tolu diphenylbenzene isobutyl vanadium tricarbonyl; 1,3,5-tri ene methyicyclopentadienyl trichlorotitanium; o-xylene ethylbenzene iodovanadium triammonia; 1-butyl-3-iso ethylcyclopentadienyl tricyanotitanium; ethylbenzene n propylbenzene cyanovanadium tris-sec-dodecylamine; cz octylcyclopentadienyl trihydrotitanium; diphenyl dimeth ethylallylbenzene trihydrovanadium diphenylenediamine; ylcyclopentadienyl trimethyltitanium; n-butylbenzene in benzene chlorovanadium tris-tert-phenylamine; p-cymene denyl tri-n-hexyltitanium; cumene titanium dinitrosyl car ethylcyclopentadienyl niobium ammonia; toluene niobium bonyl; isopropylbenzene titanium dinitrosyl ammonia; di methylenediamine nitrosyl; and hexamethylbenzene do phenylmethane titanium tricarbonyl tert-phenylamine; p decyltantalum tricarbonyl. xylene titanium dinitrosyl N-methyl-N-phenylamine; Example VIII toluene titanium triammonia; mesitylene ethylcyclopen 50 Dibenzene vanadium, prepared by the reaction of ben tadienyl cyanotitanium; mesitylene zirconium triammonia; Zene with vanadium chloride in the presence of aluminum isodurene pentachloro cyanohafnium; pentamethylben and aluminum chloride, followed by reduction of the re zene indenyl dibromotitanium; benzene titanium nitrosyl Sulting dibenzene vanadium cation, is treated under pres bis-methylisonitrile; prehnitene tricyano zirconium bis-sec sure with NO. NO pressure from 10 to 1000 p.s.i.g. is butylamine; durene amylcyclopentadienyl hafnium meth employed and the reaction temperature is varied from 0 yl-dichlorophosphine etc. to 150 C. to produce an optimum yield of benzene vana Example VI dium dinitrosyl having the formula CHVCNO). - The procedure of Example IV is repeated using zir Example IX conium iodide as the metal reactant, and boron trifluoride 60 Ten parts of chromium carbonyl, 20 parts of benzene, as the Friedel-Crafts catalyst. In this example para-xylene 20 parts of 5-trichloromethylcyclopentadiene and 70 parts is employed as the aromatic compound. Para-xylene Zir of diethyleneglycol dimethylether are charged to an evac conium tetracarbonyl results. uated reaction vessel. The reaction mixture is then heated Still other aromatic Group IV-B metal coordination at reflux (with stirring under nitrogen) for 10 hours. The compounds of this invention include allylbenzene titanium 65 vessel is then cooled, the contents are discharged and fil dinitrosyl trichlorophosphine; n-amylbenzene titanium tered. The solvent is removed from the filtrate by heating dinitrosyl ethylene-diamine; tert-butylbenzene titanium in vacuo to give a good yield of benzene chromium tri tetracarbonyl; sec-butylbenzene titanium tricarbonyl am chloromethylcyclopentadiene. monia; benzene zirconium dicarbonyl trimethylenedia mine; toluene pentaethyl hafnium nitrosyl; mesitylene tri Example X methyl pentacyano hafnium; 1,3-di-n-propylbenzene in Five parts of dicyclopentadienyl titanium dicarbonyl, 50 denyl tricyano titanium; p-phenyl toluene methylcyclo parts of mesitylene and 50 parts of methylcyclopentadiene pentadienyl trihydrozirconium; mesitylene hafnium tetra are charged to an evacuated autoclave equipped with inlet 3,5-diaminoheptane; oz-methylbutylbenzene dichlorotita and discharge ports, stirring means, pressure control means nium, and the like. and temperature control means. The autoclave is pressur 3,361,779 9 3) ized with nitrogen to 800 p.s.i.g. and the autoclave is pounds of this invention as polymerization catalysts; the heated to 100° C. The temperature is maintained at 100 parts are given by weight. A sealed autoclave provided C. for 5 hours during which time the reaction mixture is with a stirrer is charged in the absence of moisture or air stirring continuously. The autoclave is then cooled, the with 250 parts of hexane, 20 parts of active aluminum, 2 nitrogen is vented off and the contents are discharged. The parts of aluminum chloride and 12 parts of toluene solvent is removed by heating the reaction product in titanium tetracarbonyl. The aluminum is prepared by vacuo. The residues are then distilled to give a good yield cutting particles from a rod of aluminum, using a ro of mesitylene titanium cyclopentadiene dicarbonyl. tating cutter blade. The cutting was accomplished below Example XI the surface of hexane solvent so as to prevent contact Three parts of dibenzene vanadium, 20 parts of cyclo of the freshly cut aluminum surfaces with air. The pentadiene and 20 parts of hexane are charged to an aluminum cuttings are removed from the solvent and evacuated autoclave equipped as in the previous example. added to the autoclave. It is not necessary to add any The autoclave is pressurized with carbon monoxide to aromatic compound to initiate polymerization. The auto 500 p.s.i.g., and heated to 150° C. This temperature is clave is closed and pressurized with 20 parts of ethylene maintained for 6 hours during which time the reaction 5 giving an initial (not equilibrium) pressure of about 20 mixture is continuously agitated. The autoclave is then p.s.i.g. The temperature of the autoclave is thereafter cooled, carbon monoxide gas is vented off and the con increased to 90° C. and maintained at this temperature tents are discharged. The solvent is removed by heating for 3 hours. The autoclave is then cooled to 25 C. and the reaction product in vacuo. The residues are distilled additional ethylene is charged to provide an equilibrium to give a good yield of benzene vanadium cyclopentadiene 20 pressure of 600 p.s.i.g. Thereafter, the temperature of carbonyl. the autoclave is again raised to 90° C. The pressure in Other compounds of this invention include benzene the autoclave increases upon heating to about 700 p.s.i.g. chlorovanadium dicarbonyl; toluene dicyanovanadium and heating is continued. The temperature then increases nitrosyl; mesitylene pentacyanovanadium; hexylbenzene due to reaction and the pressure drops. Heating is then tricyano vanadium nitrosyl; benzene trifluorovanadium ni 25 discontinued. The autoclave is then allowed to stand for trosyl; benzene trifluorovanadium bis-sec-phenylamine; about 16 hours. toluene pentamethyl tantalum; toluene pentabromo chro This crude product is comminuted by vigorous agita mium; hexamethylbenzene pentacyano tungsten; m-dipro tion in the presence of an equal weight solution of pylbenzene indenyl vanadium; toluene methylcyclopenta methanol and 6 moles hydrochloric acid, using one part dienyl vanadium; mesitylene bromoniobium 3,5-diamino 30 of polymer per 20 parts of solution. The procedure is hexane; 2-phenylpentane dichloro tantalum nitrosyl; ben repeated a total of 3 times. The solids (having the in Zeine vanadium nitrosyl phenylamine; p-Xylene vanadium organic impurities removed) are then separated by filtra nitrosyl methylethylamine; ally benzene niobium nitrosyl tion from the alcoholic solution, rinsed with acetone, and trichlorophosphine; n-amylbenzene chloroniobium meth dried in a vacuum oven at 65 C. The so-purified solid ylene diamine; benzene cyanotantalum dicarbonyl; and polymer had a melting point above 120° C. which is tert-butylbenzene trihydro tantalum ammonia. determined using a standard polarizing microscope hav Example XII ing a heating stage. The procedure of Example VII is repeated employing a The aromatic metal coordination compounds of this tantalum halide in lieu of the vanadium chloride. After invention may be incorporated in paints, varnish, print carbonylation to cyclopentadienyl tantalum tetracarbonyl, 40 ing inks, synthetic resins of the drying oil type, oil enamels benezene cyclopentadienyl tantalum carbonyl is produced and the like, to impart excellent drying characteristics to by reaction with benzene in the presence of a slight excess such compositions. Generally speaking from 0.01 to 0.05 of aluminum chloride. percent of metal as a compound of this invention is Still other examples of the novel Group V-B metal beneficially employed as a dryer in such a composition. compounds of this invention include toluene methyl Good results are also obtained when the compounds of ethylcyclopentadienyl hydrovanadium; p-xylene ethylcy this invention are used in conjunction with lead naph clopenadienyl ethylniobium; ethylbenzene tetrabutyl tan thanate or cobalt naphthanate and similar drying agents. talum ammonia; diphenyl vanadium tricarbonyl; benzene For example, to a typical varnish composition contain indenyl cyanovanadium; benzene vanadium dinitrosyl; ben ing 100 parts of ester gum, 173 parts of tung oil, 23 parts zene vanadium tricarbonyl; ethylbenzene tricyanovanadi 50 of linseed oil and 275 parts of white petroleum naphtha um nitrosyl; mesitylene dibromoniobium bis-butyldibro is added 3.5 parts of benzene zirconium tetracarbonyl mophosphine; toluene cyclopentadienyl chlorotantalum; and 2.0 parts of lead naphthanate. The resulting varnish benzene niobium dicarbonyl nitrosyl; toluene pentaethyl composition is found to have excellent drying character niobium carbonyl; mesitylene dihexyl pentacyano tanta istics. Good results are also obtained when other drying lum; propylbenzene indenyl dichloro tantalum; toluene 5 5 oil compositions and other compounds of this invention methylcyclopentadienyl dihydro tantalum, and the like. are employed. The novel aromatic metal compounds of this invention Other compounds of this invention which may be em can be employed as polymerization catalysts in the polym ployed as drying agents, catalysts and metal sources in erization of olefins; as drying agents in drying oil com clude benzene cyclopentadienyl chromium; toluene meth positions and as metal sources in gas-phase plating opera 60 ylcyclopentadienyl molybdenum; oxylene ethylcyclopen tions. The Group IV-B metals and particularly titanium tadienyl chromium; ethylbenzene n-octylcyclopentadienyl compounds of this invention are preferred as polymeriza niobium; diphenyl dimethylcyclopentadienyl vanadium; tion catalysts. They are often employed together with n-butylbenzene indenyl vanadium; cumene tungsten nitro aluminum and aluminum halides in the pressure polym Syl carbonyl; isobutylbenzene molybdenum nitrosyl diam erization of Such unsaturated compounds as ethylene. monia; diphenylmethanol chromium nitrosyl tert-phenyl For use as dryers the zirconium and chromium compounds amine; p-Xylene chromium nitrosyl N-methyl-N-amyla of this invention are preferred, whereas in gas plating mine; allylbenzene vanadium nitrosyl tribromophosphine; operations the tantalum, chromium and tungsten com isoamylbenzene cyano tantalum ethylenediamine; n-butyl pounds find the greatest utility as they produce higher benzene ethyl molybdenum dicarbonyl; sec-butylbenzene acid resistance coatings on the surface to which bonded. trichloro chromium carbonyl; benzene methyl vanadium In addition the compounds of this invention are useful dicarbonyl; toluene diethyl niobium nitrosyl; mesitylene as intermediates in the preparation of other organo trimethyl dicyano tungsten; benzene zirconium cyclo metallics, drugs, insecticides, etc. octatetraene; toluene cyclopentatrienyl vanadium; benzene R The following is given to illustrate the use of com 75 molybdenum tris-trichloroamine; benzene tetrahydromo 3,361,779 2 lybdenum phenylamine; benzene hexachlorotungsten; o 11. The compound of claim wherein the metal is Xylene tetranonylvanadium ethylphosphine; p-cymene bonded to a single aromatic molecule and in addition is amylcyclopentadienyl tungsten; toluene tricyanotantalum bonded to a cyclopentadienyl hydrocarbon radical having nitrosyl; pentamethylbenzene ethylindenyl tungsten; ben 5 to about 13 carbon atoms which donates 5 electrons to the metal atom for bonding. Zene vanadium nitrosyl bis-methyl isonitrile, and the like. 5 12. The compound of claim 1 wherein the metal is Having fully described the novel compounds of the bonded to a single aromatic molecule and in addition is present invention, modes for their preparation and meth bonded to a cycloheptatrienyl hydrocarbon radical having ods for their employment, we do not intend that our in 7 to about 15 carbon atoms which donates seven electrons vention be limited except within the spirit and scope of to the metal atom for bonding. the appended claims. - () 13. As compositions of matter the stable organometal We claim: 1. A nonionic complex aromatic metal compound of a lic carbonyls having the formula: metal selected from the class consisting of Groups IV-B, V-B and VI-B metals having a single aromatic molecule bonded to the metal through the carbon atoms of the benzene ring by donation of 6 electrons from said ring to said metal, which compound is stabilized by additional covalent bonding to dissimilar non-aromatic electron do nating groups, such that the total number of electrons donated by said aromatic molecule and said dissimilar wherein M is selected from the group consisting of chro electron donating groups plus the atomic number of said mium, molybdenum and tungsten, M is bonded to the metal equals an integer having a value of from 2 less organic group through six electrons of the benzeniod ring than the atomic number of the next higher rare gas to system, said organic group contains not more than about the value of the next higher rare gas. 18 carbon atoms, and each R group is selected from the 2. A nonionic complex aromatic metal compound hav 25 class consisting of hydrogen, alkyl and aryl. ing the formula 14. The compound of claim 5 wherein said metal is AMQ chromium. wherein M represents an atom of a metal selected from 15. The compound of claim 5 wherein said metal is the class consisting of Groups IV-B, V-B and VI-B molybdenum. metals, A represents an aromatic compound having a ben 30 6. The compound of claim 5 wherein said metal is Zene molecule coordinated to said metal atom through tungsten. the carbon atoms of the benzene ring by donation of 6 17. A stable organochromium carbonyl having the electrons from said ring to said metal, and Q represents a formula: discrete combination of non-aromatic electron donor groups involved in bonding with said metal atom, such 3 5 that the total number of electrons associated with said metal atom equals an integer having a value of from 2 less than the atomic number of the next higher rare gas to the value of the next higher rare gas. 3. An nonionic complex aromatic metal compound hav 40 ing the formula wherein the chromium is bonded to the organic group AM(B)(C) through six electrons of the benzeniod ring system, said wherein M represents a metal atom selected from the organic group contains not more than about 18 carbon class consisting of Groups IV-B, V-B and VI-B metals, atoms, each R represents a member selected from the class A represents an aromatic compound having a benzene nu consisting of hydrogen, alkyl and aryl, and at least one of cleus coordinated to said metal atom through the carbon said R's is selected from the class consisting of alkyl and atoms of the benzene ring by donation of 6 electrons from aryl. said ring to said metal, and B and C represent electron 18. Tetrahydronaphthalene chromium tricarbonyl. donating groups which donate from 1 to 8 electrons each to the metal atom, b is an integer ranging from 1 to 8, and 50 References Cited c is an integer ranging from 0 to 4, such that the atomic UNITED STATES PATENTS number of the metal M, plus b times the number of elec 2,409,167. 10/1946 Veltman ------260-429 trons donated by B, plus c times the number of electrons donated by C plus the 6 electrons donated by the aromatic 2,818,416 12/1957 Brown et al. ------260-429 molecule A equals an integer having a value of from 2 5 5 OTHER REFERENCES less than the atomic number of the next higher rare gas Z. Anorg. Chem. 221, pp. 337-348 (1935). to the value of the next higher rare gas. Piper et al., J. Inorg. Nucl. Chem., vol. 3, pp. 104-124, 4. The compound of claim wherein said metal achieves September 1956. - the electron configuration of the next higher rare gas. Chem. Abstracts, vol. 50, No. 10, 12036, Sept. 10, 1956. 5. The compound of claim 1 wherein said metal is a 60 Angew. Chen., 68, p. 462 (1956). Group VI-B metal. JACS, 79, 5826 (1957). 6. Mesitylene chromium tricarbonyl. Chemistry and Industry, Mar. 3, 1956, pp. 153-154. 7. The compound of claim wherein the metal atom Fischer et al., Chem. Berichte, 89, pp. 1809-1815 is bonded to a single aromatic molecule and in addition (1956). is bonded to a cyclic polyolefin which contributes 4 elec Fischer et al., Chem. Berichte, 90, pp. 1725-1730 trons to the metal atom for bonding. (1957). 8. The compound of claim 7 wherein the cyclic poly Fischer et al., “Angew. Chem.' 1957, 69, 715. olefin is a cyclopentadiene molecule. Nicholls et al., “Proceedings of The Chemical Society” 9. The compound of claim 8 wherein the said metal (London), p. 152, May 1958. achieves the electron configuration of the next higher rare gaS. TOBIAS E. LEVOW, Primary Examiner. 10. The compound of claim wherein the metal is ABRAHAM H. WINKELSTEIN, Examiner. bonded to a single aromatic molecule and in addition is R. S. AULL, W. J. VANBALEN, H. M. S. SNEED, bonded to a carbonyl group which donates two electrons Assistant Examiners.

to the metal atom for bonding. -