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United States Patent (19) 11 Patent Number: 5,922,895 Tzou Et Al

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United States Patent (19) 11 Patent Number: 5,922,895 Tzou Et Al USOO5922895A United States Patent (19) 11 Patent Number: 5,922,895 TZOu et al. (45) Date of Patent: Jul. 13, 1999 54 AMINE BORANE COMPLEXES AND 3,220,972 11/1965 Lamoreaux ............................ 260/46.5 PHOSPHINEBORANE COMPLEXES AS 3.658,866 4/1972 Tsuji et al. .............................. 556/479 CATALYST FOR HYDROSLATION 5,191,103 3/1993 Mehta et al. ............................ 556/479 5,262,554 11/1993 Bank ................................... 556/479 X 75 Inventors: Ming-Shin Tzou, Midland, Mich.; 5,621,129 4/1997 Hayashi et al. ..................... 556/479 X Yasushi Sugiura, Chiba Prefecture, 5,654,455 8/1997 Pastor et al. ........................ 556/479 X Japan 73 Assignee: Dow Corning Corporation, Midland, Primary Examiner Paul F. Shaver Mich. Attorney, Agent, or Firm Melvin D. Fletcher 21 Appl. No.: 09/062,076 57 ABSTRACT 22 Filed: Apr. 17, 1998 A hydrosilation method comprising contacting a Silicon 6 hydride with an unsaturated reactant in the presence of a 3. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - c". catalysts Selected from the group consisting of amine borane 58 Field of search - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 556/679 complexes and phoshineborane complexes. The catalysts are especially useful for Selectively hydrosilating unsaturated 56) References Cited organic compounds with an internal unsaturated bond to increase the desired hydrosilation product yield. U.S. PATENT DOCUMENTS 2,823,218 2/1958 Speier et al. ......................... 260/448.2 17 Claims, No Drawings 5,922.895 1 2 AMINE BORANE COMPLEXES AND the group consisting of alkyls comprising one to about PHOSPHINEBORANE COMPLEXES AS 20 carbon atoms, cycloalkyls comprising four to about CATALYST FOR HYDROSLATION 12 carbon atoms, and aryls, X is a halogen, a-0 to 3, and a+b=1 to 4, and BACKGROUND OF INVENTION (B) an unsaturated reactant Selected from the group con Sisting of The present invention is a hydrosilation method compris (i) Substituted and unsubstituted unsaturated organic ing contacting a Silicon hydride with an unsaturated reactant compounds, in the presence of a catalyst Selected from a group consisting (ii) Silicon compounds comprising Substituted or of amine borane complexes and phosphineborane com unsubstituted unsaturated organic Substituents, and plexes. The catalyst are especially useful for increasing (iii) mixtures of (i) and (ii); Selectivity for the hydrosilation of unsaturated reactants in the presence of a catalyst Selected from the group con where the unsaturation is in the internal portion of the Sisting of amine borane complexes described by formula reactant's Structure. RNBH and phoshineborane complexes described by It is known in the art to produce organosilicon compounds formula by reacting a Silicon hydride containing compound with an 15 RPBH, where each R is independently selected from unsaturated organic compound in the presence of a catalyst. the group consisting of alkyls comprising one to about This reaction is typically referred to as hydrosilation or 10 carbon atoms, arylalkyl, and aryls. hydrosilylation. Typically the catalyst is platinum metal on The contacting of the silicon hydride with the unsaturated a Support, a platinum compound generally in a Solvent, or a reactant can be effected in Standard type reactors for con platinum complex. ducting hydrosilation processes. The contacting may be conducted as a continuous, Semi-continuous, or batch pro In Speier et al., U.S. Pat. No. 2,823,218, a method for the CCSS. production of organoSilicon compounds by reacting an Si-H Silicon hydrides useful in the present method are with a compound containing aliphatic carbon atoms linked described by formula (1), where each R is independently by multiple bonds in the presence of chloroplatinic acid is 25 Selected from the group consisting of alkyls comprising one taught. Lamoreaux, U.S. Pat. No. 3,220,972, teaches a to about 20 carbon atoms, cycloalkyls comprising four to Similar process, however the catalyst is a eaction product of about 12 carbon atoms, arylalkyls, and aryls, a=0 to 3, b=1 chloroplatinic acid. to 3, and a+b=1 to 4. R' can be, for example, a substituted One major limitation platinum has as a hydrosilation or unsubstituted alkyl Such as methyl, ethyl, propyl, butyl, catalyst is that it is not particularly effective hydrosilating pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, and unsaturated organic compounds with an internal unsaturated dodecyl; a cycloalkyl Such as cyclopropy, cyclobutyl, bond and is known to produce multiple hydrosilation prod cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl, an ucts that are difficult to separate. In addition to multiple aryl Such as phenyl, tolyl, and naphthyl. Preferred is when hydroSilation products, when platinum catalyst is used to R" is methyl. hydroSilate unsaturated organic compounds with an internal 35 In formula (1), it is preferred that each R be indepen unsaturated bond, often the result is migration of the unsat dently Selected from a group consisting of alkyls comprising urated bond Such that silyl group bonds to the terminal about one to six carbon atoms. Even more preferred is when carbon. each R' is methyl. X is a halogen and most preferred is when The present invention provides a method for hydrosilating X is a chlorine atom. unsaturated reactants for the preparation of organosilanes. 40 Examples of silicon hydrides described by formula (1) The inventors have unexpectedly discovered that catalysts which may be useful in the present method include Selected from the group consisting of amine borane com trimethylsilane, dimethylsilane, trie thylsilane, plexes and phosphineborane complexes can be used in dichlorosilane, trichlorosilane, methyidichlorosilane, hydroSilation reactions. More particularly, these catalysts dimethyl chloro Silane, ethyl dichloro Silane, can Selectively hydrosilate unsaturated organic compounds 45 cyclopentyldichlorosilane, methylphenylchlorosilane, (3,3, with internal unsaturated bond to increase the desired 3-trifluoropropyl)dichlorosilane, and methylchlorosilane. hydroSilation product yield. Examples of preferred silicon hydrides described by formula (1) include methyldichlorosilane, trichlorosilane and dichlo SUMMARY OF INVENTION rosilane. The present invention is a hydrosilation method compris 50 The Silicon hydride is contacted with an unsaturated ing contacting a Silicon hydride with an unsaturated reactant reactant Selected from a group consisting of (i) Substituted in the presence of a catalyst Selected from the group con and unsubstituted unsaturated organic compounds, (ii) Sili Sisting of amine borane complexes and phoshineborane con compounds comprising Substituted and unsubstituted complexes. The catalysts are especially useful for Selec unsaturated organic Substituents, and (iii) mixture of (i) and 55 (ii). For purpose of this invention, “unsaturated” means that tively hydrosilating unsaturated organic compounds with an the compound contains at least one unsaturated bond. internal unsaturated bond to increase the desired hydrosila More specific examples of the unsaturated reactants use tion product yield. ful in the present method include unsubstituted cycloalkene DESCRIPTION OF INVENTION compounds comprising at least four carbon atoms, Substi 60 tuted cycloalkene compounds comprising at least four car The present invention is a hydrosilation method compris bon atoms, linear alkene compounds comprising two to ing contacting a Silicon hydride with an unsaturated reactant about 30 carbon atoms, branched alkene compounds com in the presence of a catalyst Selected from the group con prising four to about 30 carbon atoms, alkyne compounds Sisting of amine borane complexes and phoshineborane comprising about two to 30 carbon atoms, and mixtures of complexes. The method comprises contacting 65 two or more of any of the above. (A) a silicon hydride described by formula R.H.SiX. The Substituted and unsubstitued cycloalkene compounds a-b (1) where each R is independently Selected from useful in the present method are those containing one or 5,922.895 3 4 more unsaturated bond in the ring. The unsubstituted butene and trichlorosilane was prepared in a glass tube cycloalkene compounds may be, for example, cyclobutene, without catalyst. The tube was heat Sealed under an argon cyclopentene, cyclohexene, cycloheptene, cyclooctene, 1,3- purge and heated at 250 C. for one hour. At the end of one cyclohe X a die ne, 1,3,5-cyclohept a trie ne, hour the tube was cooled and the contents analyzed by C 1-methylcyclopentene, 4-phenylcyclohexene, and nuclear magnetic resonance spectroscopy (NMR) and gas 3-methylcyclopentadiene. The preferred cycloalkene com chromatography using a thermal conductivity detector (GC pounds are cyclohexene and cyclopentene, with cyclohex TC). The GC-TC analysis indicated the formation of 2.8 area ene being the most preferred. percent 2-methyl-3-trichlorosilylbutane under the GC-TC Unsaturated reactants useful in the present method include Substituted and unsubstituted organic compounds trace. including alkenes, Such as, 1-hexene, 1,5-hexadiene, trans 1O 2-hexene, 1-methyl-cyclohexene, 2-methyl-2-butene, 2,3- EXAMPLE 2. dimethyl-2-butene, 1,3-butadiene, 4-methyl-1,3-pentadiene, Evaluation of the hydrosilation of 2-methyl-2-butene with 2-methyl-3-hexene, 3-methyl-3-hexene, 3-ethyl-2,2- trichlorosilane catalyzed by trimethylamine borane. A dimethyl-3-heptene,
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