3,095,436 United States Patent Office Patented June 25, 1963 1. 2 that my compounds can be recrystallized from ethers 3,095,436 ALKAL METAL-ETHER COMPLEX SALTS OF A which are not the same as the complexed ether without NITROGENOUS GROUP WIB METAL PENTA loss of the complexed ether. To illustrate, the compound CARBONYLANON Raymond E. Magian, Detroit, Mich., assignor to Ethyl sodium bis(dimethoxyethane) chromium pentacarbonyl-(S) Corporation, New York, N.Y., a corporation of Vir can be recrystallized from diethyl ether without removal ginia of the complexed dimethoxy ethane. No Drawing. Filed Apr. 11, 1961, Ser. No. 102,123 My compounds can be depicted as having the follow 11 Claims. (C. 260-438) ing generic formula: 10 This invention relates to novel organometallic com pounds. More specifically, the invention relates to ionic compounds of group VIB metals in which an anion in which A is an alkali metal cation (preferably sodium), having the formula: Y is a bidentate non-cyclic ether, and x is an integer ranging from 2 to 4. Preferably, x is two, M is a (M(CO)5(S) 5 group VIB metal, i.e., chromium, molybdenum, and is bonded to a cation. In the above formula, M is a tungsten, and the group - group VIB metal i.e., chromium, molybdenum, and tungsten. Group (S) 20 contains one carbon and one nitrogen atom, one of (S) which is bonded to the group VIB transition metal M. is written with the C above the N so as not to denote a Examples of compounds within the ambit of the above preference of the metal atom, M, toward either the formula are carbon atom or nitrogen atom for bonding. In reality, sodium bis (1,2-dimethoxyethane) chromium pentacarbonyl-(S) there may well be a preference toward either the carbon 25 or nitrogen atom for bonding. I have not been able to sodium bis(1,3-diethoxy propane) molybdenum pentacarbonyl-(S) determine as yet, however, what if any, preference exists. The ionic compound in which the above anion is bonded sodium bis(1,2-dipropoxy ethane) tungsten pentacarbonyl-(S) to a cation is stabilized by the presence of certain speci fied ethers in the molecule. Also included in my inven 30 and the like. tion is a method for making the above mentioned com My ionic compounds are formed by reacting an ap pounds. propriate cyanide salt such as sodium cyanide, potassium An object of this invention is to provide novel organo cyanide, lithium cyanide, or calcium dicyanide with a metallic compounds of group VIB metals. A further group VIB metal hexacarbonyl in the presence of a 35 specified ether as described above. My process is pref object is to provide compounds in which a cation is erably carried out in the presence of an inert atmosphere bonded to an anion having the formula: such as nitrogen, argon, krypton, neon, or the like. Preferably, nitrogen is used as the inert atmosphere since (M(CO)5(S) it is cheaper and more plentiful than other of the enum as defined above, which compound is stabilized by the 40 erated inert gases. The reaction temperature is not presence of specified ethers in the molecule. An addi critical but preferably ranges from about 80° C. to about tional object of this invention is to provide a method for 150° C. making the above mentioned compounds. Still further My process is normally conducted at atmospheric objects will become apparent from the following dis pressure but may be conducted at higher pressures if cussion and claims. 45 desired. In the event that the non-cyclic bidentate ether The objects of my invention are accomplished by re solvent is relatively low boiling, it may be advantageous acting a cyanide salt with a group VIB metal-hexacarbonyl to carry out the reaction under pressure since this en compound in the presence of a specified solvent. Ap ables the use of higher temperatures without solvent loss. plicable cyanide salts which may be employed in form During my process, I preferably agitate the reaction mix ing my novel compounds are alkali metal-cyanide salts 50 ture since this affords a more even reaction rate, a such as sodium cyanide, potassium cyanide, lithium shorter reaction time, and facilitates removal of carbon cyanide, rubidium cyanide, and cesium cyanide. Also, monoxide from the reaction mixture. I can employ alkaline earth metal-cyanide salts as re The relative quantities of reactants used are not critical. actants. An excess of either the group VIB metal-hexacarbonyl or As stated above, the reaction is carried out in the 55 the cyanide salt may be used if desired. The non-cyclic presence of a specified solvent. In my experimental bidentate ether reactant is employed in the reaction in a work, I found the nature of the solvent to be critical large excess, i.e., in solvent quantities. The time required to the success of the reaction. Applicable solvents which for the reaction is determined by the other reaction vari I can employ are the bidentate non-cyclic ethers such ables employed. Thus, an increase in the reaction tem as dimethoxyethane, diethoxyethane, dipropoxy propane, 60 perature and an increase in the degree of agitation will and the like. These solvents stabilize the ionic com cause a proportionate decrease in the reaction time which pound which is formed between the cation which is an is required. In practice, it is not difficult to determine the alkali metal, and an anion having the formula: reaction time with reasonable accuracy. This is done by determining the amount of gas evolved from the reaction (M(CO)5(S)) 65 mixture. When a quantity of gas is evolved which is The compounds produced by my process are quite equal to the displacement of one equivalent of carbon unique and differ markedly from conventional etherates. monoxide from the group VIB metal hexacarbonyl re In a conventional etherate, the ether is bound loosely actant, this shows that the reaction is essentially complete. within the molecule such that it is easily removed. In The products of my reaction are, in general, solids contrast, the bidentate ether present in my ionic com 70 -which are crystalline in nature. They are readily sepa pounds is firmly bound within the molecule so that it rated from the reaction mass by conventional means such cannot be easily removed. As an example, I have found as evaporation of solvent under vaccum followed by 3,095,436 3 4. crystallization and filtration of product. To illustrate filtered and a small quantity of petroleum ether is added further the scope of my process and the products produced to the filtrate. The addition of the petroleum ether causes thereby, there are presented the following examples in the precipitation of the product which all parts and percentages are by weight unless otherwise indicated. sodium-bis(1,3-dimethoxy propane) -tungsten-pentacarbonyl-(S) Example I The compound is separated by means of filtration after A mixture comprising 11.0 grams of chromium hexa which it is washed with petroleum ether and recrystallized carbonyl, 2.45 grams of sodium cyanide and 200 mls. of from diethyl ether. 1,2-dimethoxy ethane was heated at reflux under nitrogen When Example III is repeated employing lithium cya for 7 hours. During this time, 1150 mls. of gas were IO nide or cesium cyanide in place of sodium cyanide, the evolved. The orange reaction mixture was then filtered corresponding lithium or to remove a small quantity of unreacted sodium cyanide. The solvent was removed from the filtrate at reduced pres cesium-dinnethoxy propane-tungsten-pentacarbonyl-( S) sure to give 13.5 grams of yellow solids. These were re crystallized several times from diethylether to yield al compounds are obtained. Similarly, when an alkaline most colorless crystals having a melting point of 62-64 earth metal cyanide is employed as the reactant, there C. The crystals were stable in air for short periods of are obtained the time; they were soluble in water and ether, but insoluble alkaline earth metal-dimethoxy propano-tungsten-pentacarbonyl-(S in petroleum ether and n-hexane. The infrared spectrum of the crystalline compound showed a 20 compounds. As shown in the preceding examples, my invention pro metal-(S) vides a variety of alkali metal salts of a group VIB metal bond at 4.8 microns and metallocarbonyl bands at 4.9, 5.2, and 5.4 microns. Dimethoxy ethen bands were observed pentacarbonyl-(S) anion at 9.0 and 9.2 microns. On analysis there was found: C, 39.7; H, 4.93; N, 4.12; Na, 5.34; Cr, 12.7. Calculated In each case, the salt is stabilized by the presence of a non-cyclic bidentate ether. Unlike well-known etherates for C14H2ONNaCr: C, 39.9; H, 4.80; N, 3.34; Na, 5.46; of the prior art, the non-cyclic bidentate ether present in Cr, 12.4 percent. On the basis of the above elemental my compounds is an integral part of the compound and is analysis and infrared spectrum, the compound was clearly 30 identified as not easily removed. Thus, my compounds can be re crystallized from an ether solvent without loss of the corn Sodium bis (1,2-dimethoxyethane) chromium pentacarbonyl-(S) plexed non-cyclic bidentate ether. A utility for my compounds is as chemical intermedi When Example I is repeated employing potassium cya ates. In this use, my compounds can be employed in the nide, lithium cyanide, rubidium cyanide, or cesium cya 35 formation of other useful products which, in turn, can be nide in place of the sodium cyanide reactant, there are converted to well-known organic compounds. To illus obtained the corresponding potassium, lithium, rubidium, trate, there is presented the following example in which O all parts and percentages are by weight unless otherwise cesium 1,2-dimethoxy ethane-chronium pentacarbonyl-(S) 40 indicated. compounds. Likewise, when molybdenum hexacarbonyl Example IV or tungsten hexacarbonyl are employed in place of chro A mixture comprising 12.6 grams of mium hexacarbonyl in Example I, there are obtained the compounds sodium bis(dimethoxyethane) chronium pontacarbonyl-(S) sodium bis(1,2-dimethoxyethane) molybdenum pentacarbonyl-(S) 45 as prepared in Example I, 4.2 grams of benzoyl chloride, and 150 mls. of diethyl ether was stirred for two days at and room temperature under nitrogen. The Sodium chloride sodium bis-(1,2-dimethoxyethane) tungsten pentacarbonyl-(S) precipitate which had formed was then filtered off from 50 the reaction mass and solvent was removed from the Example II filtrate at reduced pressures to give an orange residue A mixture comprising one mole of molybdenum hexa which was extracted with petroleum ether. Cooling of carbonyl and one mole of sodium cyanide in 1,2-di the extracts followed by filtration gave 3.5 grams of orange propoxy ethane solvent is heated for four hours at 120 solids. This constituted a 37 percent yield of product. C. under nitrogen. The reaction product is then dis The solids were recrystallized from petroleum ether to charged and filtered. A small quantity of petroleum 55 give orange crystals having a melting point of 84-86 C. ether is added to the filtrate and there is precipitated the which were soluble in organic solvents but insoluble in product water. The crystalline product was readily sublimed using sodium bis(1,2-dipropoxy ethane) molybdenum pentacarbonyl-(S) a warm water bath (50° C.). The infrared spectrum of 60 the product showed major peaks at 4.75, 5.2, and 6.0 The product is filtered and washed with petroleum ether microns. Magnetic measurements indicated that the prod after which it is recrystallized from diethyl ether to give uct was diamagnetic. The product was quite air stable a good yield of pure product. and little change was noted after it had stood for several When Example II is repeated employing lithium cya hours in air at room temperature. On analysis there Was nide or potassium cyanide, in place of sodium cyanide, 65 found: C, 48.0; H, 1.45; N, 4.45; Cr, 16.2 percent with a the corresponding lithium and molecular weight of 349 (Signer method). Calculated for CHONCr: C, 48.3; H, 1.55; N, 4.33; Cr, 16.1 per potassium-dipropoxy ethane-molybdenum-pentacarbonyl-(S) cent with a molecular weight of 323. On the basis of the product's elemental analysis, infrared spectrum, and mo compounds are obtained. lecular weight, it was determined to be the compound Example III 70 A mixture comprising one mole of tungsten hexa chromium-pentacarbonyl-benzoyl-(S) carbonyl and one mole of sodium cyanide in 1,3-dimethoxy In a subsequent run when the reaction time was increased propane solvent is heated for 6 hours at 100° C. under to five days, the yield of product was increased to 54 nitrogen. The reaction product is then discharged and 75 percent. 8,095,436 5 6 Example V ing the film to the substrate material is to lightly coat the substrate material with the compound after which the A solution comprising 1.62 grams of coated substrate material is heated to a temperature above chromium-pentacarbonyl-benzoyl-(S) the decomposition temperature of the compound. The metal-containing films which are formed from my as prepared in Example IV, in 100 mls. of anisole was compounds have a wide variety of applications and may refluxed for 3.5 hours during which time 540 mls. of gas be used in forming conductive surfaces such as employed was evolved. This reaction was carried out under nitro in a printed circuit, in producing a decorative effect on gen. The reaction mixture became fairly dark during the a Substrate material or in forming a corrosion-resistant reaction and chromium hexacarbonyl was observed sub O coating on a substrate material. A still further utility liming in the condenser. A total of 0.3 gram of chromi for my compounds is as catalysts in the preparation of um hexacarbonyl, having a melting point of 153-154 C. organic compounds. was so isolated. The solvent was then removed from the unfiltered reaction mixture to yield an oily residue. An Having fully defined the novel compounds of my in infrared spectrum of the trap distillate indicated only vention, their mode of preparation and their many utili anisole to be present. The oily residue was evaporatively 5 ties, I desired to be limited only within the scope of the distilled overnight to give a clear viscous yellow liquid. appended claims. The infrared spectrum of this liquid indicated the possible 1. Compounds having the formula: presence of anisole, anisole chromium tricarbonyl, and p methoxybenzophenone with no evidence for the presence 20 in which A is an alkali metal cation, Y is a bidentate non of the starting material cyclic ether, and M is a group VIB metal. chromium-pentacarbonyl-benzoyl-(S) 2. The compounds of claim 1 in which M is chromium. The liquid was chromatographed on alumina to yield 3. The compounds of claim 1 in which A is sodium. anisole, 0.12 gram of anisole chromium pentacarbonyl, 4. The compounds of claim 1 in which Y is 1,2-di and 0.10 gram of p-methoxybenzophenone having a melt 25 methoxyethane. point of 60-61C. The infrared spectrum of this product 5. Compounds having the formula: was identical to that of a pure sample of p-methoxybenzo phenone. Na(Y). Or (OO)5(S) The product p-methoxybenzophenone is a well-known 30 in which Y is a bidentate non-cyclic ether. organic compound having well known utilities in organic synthesis. 6. Sodium bis(1,2-dimethoxyethane) chromium pentacarbonyl- (S) Example VI 7. Process for the preparation of the compounds of A solution comprising 1.62 grams of claim 1, said process comprising reacting an alkali metal 35 cyanide with a group VIB metal hexacarbonyl in the . chromium-pentacarbonyl-benzoyl-(S) presence of a non-cyclic bidentate ether. as prepared in Example IV, in 75 mls. of methanol was 8. The process of claim. 7 in which the group VEB refluxed for 5 hours under nitrogen. The solvent was metal hexacarbonyl is chromium hexacarbonyl. removed from the clear green-yellow solution under re 9. The process of claim 7 in which the alkali metal duced pressure, leaving a brownish-red oily residue. The 40 cyanide is sodium cyanide. residue was evaporatively distilled overnight, yielding 0.32 10. The process of claim 7 in which the non-cyclic gram of a clear liquid having a sweet ester-like odor. bidentate ether is 1,2-dimethoxyethane. The infrared spectrum of this liquid was identical to that 11. Process comprising reacting sodium cyanide with of pure methyl benzoate which conclusively established chromium hexacarbonyl in the presence of dimethoxy the product as methylbenzoate. 45 ethane. The product, methyl benzoate, as prepared in Example VI, is a well-known organic compound which is used ex References Cited in the file of this patent tensively in perfumery. A further use for my compounds is in metal plating. UNITED STATES PATENTS In this application, the compounds are thermally de 50 2,870,183 Brantley ------Jan. 20, 1959 composed in an atmosphere of a reducing gas such as 2,885,417 Heyden ------May 5, 1959 hydrogen or a neutral atmosphere such as nitrogen to OTHER REFERENCES form a group VIB metal-containing film on a substrate material. The substrate material can be heated above the J. Chem. Soc., July 1959, page 2323. decomposition temperature of the compound and brought 55 Karrer: "Organic Chemistry,” New York, 1938, pages into contact with the compound. Another way of apply 105-106, Bookcase VII.