1-Tri(phenyl, methyl)silyl-1-alkenes of the general formula RCHCHSiMe3−n Phn (where n = 1-3, R = CmH2m+1, m = 5, 6, 8, 10, and 12; Ph) have been prepared by a novel method, viz. by a very effective cross-metathesis of vinyltri(phenyl, methyl)silanes with 1-alkenes and styrene catalyzed by ruthenium and rhodium complexes. A tenfold excess of 1-alkene in the reaction mixture gave stereospecific 1-tri(phenyl
通式RCH = CHSiMe 3- n Ph n的1-Tri(苯基,甲基)甲硅烷基-1-烯烃(n = 1-3,R = C m H 2 m +1,m = 5,6,8 ,10和12; Ph)已通过一种新颖的方法制备。通过钌和铑配合物催化的乙烯基三(苯基,甲基)硅烷与1-烯烃和苯乙烯的非常有效的交叉复分解反应。反应混合物中过量十倍的1-烯烃以高达90%的高收率(进而转化为乙烯基硅烷)得到了立体定向的1-三(苯基,甲基)甲硅烷基-1-烯烃(主要为E-异构体)。产物通过光谱鉴定(IR,拉曼,1H,13 C NMR和GC-MS)方法。
Organic synthesis with reagents derived from 3R3SiMgMe and MnCl2
R3SiMgMe and MnCl2 are disclosed. (1) The manganese species reacted with terminal acetylenes to give 1,2-disilylated 1-alkenes. Mono- and bis(trimethylsilyl) acetylenes gave tri- and tetrasilylated ethenes, respectively, in good yields. Highly strained tetrakis(trimethylsilyl) ethene has now become easily accessible by this technique. (2) The reaction of alkenyl halides, alkenyl sulfides, and enol phosphates
The reaction of alkenyl halides, alkenyl sulfides, and enol phosphates with (R3Si)3MnMgMe provides vinylsilanes in good yields. The method is also applicable to the allylsilanesynthesis from allylic sulfides and ethers.
Triethylborane Induced Stereoselective Radical Addition of R<sub>3</sub>SiH to Acetylenes and Stereoselective Reduction of Alkenyl Iodides with Tris(trimethylsilyl)silane
Triethylborane induced radical addition of various organosilanes (R3SiH) to acetylenes has been studied. Among them, tris(trimethylsilyl)silane (TTMSS) proved to be the best reagent for the hydrosilylation of acetylenic compounds in terms of yield and stereoselectivity. For instance, reaction of 1-dodecyne with TTMSS at room temperature for 3 h under Et3B catalyst provided (Z)-1-tris(trimethylsilyl)silyl-1-dodecene