May 6, 1969 D. GRANT ET AL 3,442,921 PROCESS FOR THE PREPARATION OF TETRAORGANO GERMANES Filed Oct. 2, 1964

DRAWING REPRESENTATIVE OF THE FORMATION OF TETRA ORGANO GERMANUM COMPOUNDS

TIME

INVENTORS DAV D G RANT JOHN R. VAN WAZER Yzella-6aezaleazz AT TORNEY 3,442,921 United States Patent Office Patented May 6, 1969

1. 2 3,442,921. temperature of 120° C. In general the preparation of the PROCESS FOR THE PREPARATION OF alkyls and haloalkyls are carried out using TETRAORGANO GERMANES molar proportions of from 3:1 to 100:1 of the tin tetra David Grant, Ruabon, North Wales, and John R. Van alkyl relative to the germanium tetrahalide. The table Wazer, Ladue, Mo., assignors to Monsanto Company, below shows the nature of the major products which are St. Louis, Mo., a corporation of Delaware obtained in this specific example based upon germanium Filed Oct. 21, 1964, Ser. No. 405,474 tetrachloride and tin tetramethyl in the respective propor Int, C. C07f7/00, 7/22; C08g 33/20 tions set forth below. U.S. C. 260-429 6 Claims The separation of the germanium alkyl compounds is O readily carried out by distillation methods. For example the germanium alkyl and haloalkyl compounds obtained ABSTRACT OF THE DISCLOSURE by the reaction of germanium tetrachloride and tetra The compounds of the present invention yield poly methyltin have the boiling points indicated, and are mers such as by the hydrolysis of the alkyl germanium readily separated as individual components. halides to yield polyalkyl germanium oxides. The afore 5 said germanium alkyl and haloalkyl compounds are also TABLE I useful as intermediates in the manufacture of other ger manium compounds. The present invention relates to a S.S.)GeCl process for the preparation of substituted germanium Major compounds, employing a germanium tetrahalide which is 20 Proportion Product Physical Properties reacted with a substituted tin compound. 4:1------Ge(Me)4-...--- B.P., 44.3°C (740 mm.). d20, 0.9661. 8:1------GeMe3Cl.--- B.P.,in D20, 1.3882.115° C. (760 mm.). The present invention relates to a novel process for the M.P., -13° C. 25 d20, 1.2493. production of alkyl, alkenyl, haloalkyl and haloalkenyl nD20, 1,4337. germanium compounds. According to the invention there 2:2------GeMe2Cl2--- B.P., 124°C. (760 mm.). M.P., -22 C. are provided various germanium compounds having hy d20, 1.5053. mD20, 1.4600. drocarbyl radicals including alkyl and alkenyl radicals 1:3------GeMeCls---- B.P., 111° C. (760 mm.) of from 1 to 20 carbon atoms such as Ge(CH4)4 and d20, 1.7053. aromatic radicals such as phenyl, tolyl and xylyl radicals 30 nD20, 1.4685. as well as haloalkyl compounds such as Ge (C2H5)2Cl2 and other haloalkyl compounds. The hydrocarbyl groups having from 1 to 20 carbon atoms include both saturated It is found that at 300 hours the equilibrium propor and unsaturated compounds, the latter being typified by tions are about 20 mole percent of germanium tetrameth the allyl or vinyl radical, and also substituted alkyl radi 35 yl and about 15 mole percent of germanium dimethyl di cals such as the benzyl radical. , with the proportion of the germanium tetra Germanium alkyls such as germanium tetramethyl, methyl increasing with time. also known as tetramethyl germane, have been made in It is also an embodiment of the invention to determine the past by the use of a Grignard reagent or by the use the maximum production of the completely alkylated of lithium alkyls; however the direct preparation as de 40 germanium compound, in this instance germanium tetra scribed herein overcomes certain disadvantages of Such methyl by the detection of the appearance of the meth previously known methods. yl germanium trichloride and trimethyl germanium chlo The general process of the present invention is carried ride in the reaction mixture of alkylated germanium com out by admixing the desired molecular proportions of a pounds. These two compounds appear at the approximate germanium tetrahalide such as germanium tetrachloride, 45 time when the concentration of the germanium tetra , germanium tetrabromide, or methyl has reached a maximum, as shown in the drawing germanium tetraiodide, with the corresponding propor of the present patent application. This determination of tion of tetraalkyl tin. The reaction mixture is then heated the first appearance of such methyl germanium trichloride to a temperature in the range of from 30° C. to 400 C. and trimethyl germanium chloride is conducted by the 50 use of a gas chromatography test or by nuclear magnetic a preferred range being from 50° C. to 300 C. A solvent eSOaCe - is not necessary, although it is more convenient to operate In general the identification of the molecular charac in the presence of a hydrocarbon solvent, e.g., , terization of the germanium compounds of the present toluene or decane solvent or a halocarbon solvent such as invention are conducted by nuclear magnetic resonance, . The pressure which is employed is including the determination of shifts due to the higher al not critical, and the reaction may be conducted in a sealed 55 kyl groups appearing as peaks and multiplets. The ob tube or in an open reaction vessel. served peak area then provides an indication of the relative The following examples illustrate specific embodiments proportions of the various groups. of the present invention. In the present example, the optimum yield of germani Example 1 60 um tetramethyl corresponds to the first indication by gas The preparation of a germanium tetraalkyl compound, chromatography or nuclear magnetic resonance of the specifically germanium tetramethyl and the germanium methyl germanium trichloride and trimethyl germanium methyl is shown in the present example. A pres chloride. sure tube is charged with a 0.30 M solution of germanium Example 2 tetrachloride in carbon tetrachloride and 0.30 M solution 65 The preparation of tetra (n-propyl) germane and the n of tetramethyltin. In order to determine the effect of vary propyl germanium halides is shown in the following ex ing proportions a series of preparations were made. Equi ample. The procedure of Example 1 using tetrapropyl librium was determined at 300 hours and with the use of a tin and germanium tetrachloride with the ratios set forth 3,442,921 3 4. below, as well as the resultant products and their charac TABLE V terization are summarized in Table II below: Physical properties TABLE II Major product-Ph4Ge ------MP. 235 C. 5 SE)GeCl Minor products: Major Ph3GeCl ------. M.P. 115 C. Proportion Product Physical Properties PhGeCl3 ------B.P. 115/19 mm. 4:i------Ge(Pr)4----- B.P., 225° (760 mm.) The alkyl germanium compounds and the haloalkyl 3:1------GePrC1--- B.P., 227°C. O M.P., -70° C. germanium compounds of the present invention are useful dao, 1.100. in a number of relationships including the polymerization D20 14641. of olefins with the alkyl germanium as a catalytic constitu 9:2------GoPrC1---- B.P., 209.5 C. M.P., -45 C. ent used with a metal halide of group IV-A, V-B or d20, 1.275. VI-B and an organic peroxide, or molecular . in D29, 1.4725. 5 Furthermore the above compounds are readily decom l:3------GcPrCl3---- B.P., 167 C. posed in a hot tube or other heat source for the deposition d20, 1.513. of elemental germanium in the manufacture of semicon D20, 1.4779. ductors. Alternatively the evolved germanium from a hot tube decomposer may be reacted with other elements to Example- 3 20 form germanium compound semiconductors such as ger The preparation of tetra (isopropyl) germane and iso manium selenide. propyl germanium halides is shown in the present exam The germanium compounds also yield polymers such as ple. The process used is the same as in Example 1 at the by the hydrolysis of the alkyl germanium halides to yield 4:1 proportion of the isopropyl tin and germanium chlo 25 polyalkyl germanium oxides. The aforesaid germanium ride; the nature of the products and their characteriza alkyl and haloalkyl compounds are also useful intermedi tion are shown in the table below; the tetra-isopropyl ates in the manufacture of other germanium compounds, germane being obtained as the major product in best yield What is claimed is: 1. Process for optimizing the maximum production of when the presence of tri-isopropyl germanium chloride, tetra-n-propyl germane, which comprises mixing and heat and iso-propyl germanium trichloride are first detected. 30 ing together germanium tetrachloride with a 4:1 molecu TABLE III lar proportion of tetra-n-propyl tin, relative to the said Physical properties germanium compound, continuing the said heating until at least one compound selected from the group consisting Major product-(i - prop) of tri-n-propyl chlorogermane and n-propyl trichloroger Ge ------B.P. 164.5° C., 120 1.4760. 35 mane can be detected, and at this point separating the Minor products: tetra-n-propyl germane from the reaction mixture. (i-prop) 3GeCl ------. B.P. 222 C., n.20 1.472, 2. Process for optimizing the maximum production of dao 1.11. tetra-isopropyl germane which comprises mixing and heat (i-prop)2GeCl2 ------B.P. 203° C., M.P. --52 ing together germanium tetrachloride with a 4:1 molecular C., n.20 19738, d20 40 proportion of tetra-isopropyl tin, relative to the said ger 1.268. manium compound, continuing the said heating until at (i-prop) GeCls ------. B.P. 164.5° C., n.20 1.4760. least one compound selected from the group consisting of Example 4 tri-isopropyl chlorogermane and isopropyl trichloro The preparation of mixed methyl germanium bromides 45 germane can be detected, and at this point separating the is shown in the present example. The procedure is the tetra-isopropyl germane from the reaction mixture. same as in Example 1, using the proportions of 4:1 tetra 3. Process for optimizing the maximum production of methyl tin and germanium tetrabromide. The nature of tetramethyl germane which comprises mixing and heat the products and their characterization are shown in the ing together germanium tetrachloride with a 4:1 molecu table below, with the tetramethyl germane (shown in Ex 50 lar proportion of tetramethyl tin, relative to the said ample 1) being obtained as the major product in best germanium compound, continuing the said heating until at yield when the presence of trimethyl germanium bromide least one compound selected from the group consisting and methyl germanium tribromide are first detected. of trimethyl chlorogermane and methyl trichlorogermane can be detected, and at thist point separating the tetra TABLE IV 55 methyl germane from the reaction mixture. 4. Process for optimizing the maximum production of Major products: Physical properties tetraphenyl germane which comprises mixing and heat Ge(Me3)Br------B.P. 115 C., d. 1.5486, ing together germanium tetrabromide with a 4:1 molecu in 20 1.466. lar proportion of tetraphenyl tin, relative to the said GeMe2Br2 ------B.P. 153 C., d. 2.1163, 60 germanium compound, continuing the said heating until n20 1.5268. at lesat one compound selected from the group consisting GeMeBr3 ------B.P. 168 C., d. 2.6337, of triphenylchlorogermane and phenyltrichlorogermane n20 1.5770. can be detected, and at this point separating the tetra Example 5 phenylgermane from the reaction mixture. 65 5. The method for optimizing the maximum produc The present example shows the preparation of tetra tion of a compound having the formula GeR, where R phenyl germane and mixed phenyl germanium chlorides, is selected from the group consisting of alkyl and alkenyl using the procedure of Example 1 but with a proportion radicals having 1 to 20 carbon atoms, phenyl, tolyl, xylyl of 4:1 for tetraphenyl tin and germanium tetrachloride. 70 and benzyl radicals, which comprises mixing and heating The nature of the resultant products and their charac together GeX4, where X is selected from the group consist terization are shown in Table V, with the tetra-phenyl ing of fluorine, chlorine, bromine and iodine, with at least germane being obtained as the major product in best yield a 4:1 molar proportion of SnRa, relative to the germanium when the presence of triphenyl germanium chloride and compound, and continuing the said heating until at least phenylgermanium trichloride are first detected. one compound selected from the group consisting of 3,442,921 5 6 GeRX and GeRX can be detected, and at this point separating the product from the reaction mixture. References Cited 6. Process for optimizing the maximum production of UNITED STATES PATENTS tetramethyl germane, which comprises mixing and heat 3,100,217 8/1963 Bartocha ------260-448 ing together germanium tetrabromide with a 4:1 molecu lar proportion of tetramethyl tin, relative to the said ger OTHER REFERENCES manium compound, continuing the said heating until at Gilman: Organic Chemistry (vol. I), John Wiley least one compound selected from the group consisting and Sons, New York, N.Y. (1943), pp. 493-4 and p. 523. of trimethyl bromogermane and methyl tribromogermane can be detected, and at this point separating the tetra- 10 THOMAS E. LEVOW, Primary Examiner. methyl germane from the reaction mixture. A.P. DEMERS, Assistant Examiner.