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
Manganese-Catalyzed Silylmagnesiation of Acetylenes and 1,3-Dienes
作者:Jun Tang、Hiroshi Shinokubo、Koichiro Oshima
DOI:10.1246/bcsj.70.245
日期:1997.1
The treatment of 4-benzyloxy-1-butyne with PhMe2SiMgMe in the presence of a catalytic amount of MnCl2 gave a monosilylated product, (E)-PhCH2OCH2CH2CH=CHSiMe2Ph, selectively after an aqueous workup. Meanwhile, the reaction of isoprene with PhMe2SiMgMe under manganese catalysis and the subsequent addition of iodomethane afforded 4-dimethylphenylsilyl-2,3-dimethyl-1-butene in good yield.
Regiochemistry in the hydroboration of allylsilanes
作者:Ian Fleming、Nicholas J. Lawrence
DOI:10.1016/s0040-4039(00)87838-7
日期:——
The hydroboration of most types of allylsilane is highly selective for the formation of the product having the silicon and boron in a 1,3 relationship when the hydroboratingagent is 9-BBN. There is only a low degree of correlation between the difference in the chemical shifts of the trigonal carbon atoms on an alkene and the regioselectivity in hydroboration with either borane:THF or 9-BBN.