Enantioselective Aldol Reaction of Trimethoxysilyl Enol Ether Catalyzed by Lithium Binaphtholate
摘要:
(GRAPHICS)An aldol reaction of trimethoxysilyl enol ether catalyzed by lithium binaphtholate, in which water serves as an additive and plays a pivotal role in stereoselectivitles, was developed. This is the first example of an aldol reaction of trimethoxysilyl enol ether catalyzed by a chiral base.
The use of dirhodium(II) catalysts in the 1,4-hydrosilylation of alpha,beta-unsaturated ketones and aldehydes was explored. Dirhodium(II) tetrakis(perfluorobutyrate), Rh2(pfb)4, proved to be the catalyst of choice for this process, providing the corresponding silyl enol ethers in high yields.
An aldol reaction of trimethoxysilyl enol ether catalyzed by lithium binaphtholate is described. The aldol reaction of trimethoxysilyl enol ether derived from cyclohexanone under anhydrous conditions predominantly afforded the anti-aldol adduct with moderate enantioselectivity, whereas the reaction under aqueous conditions predominantly resulted in the syn-adduct and the enantioselectivity of the syn-adduct
Hydrido(triphenylphosphine)rhodium(I) as an effective catalyst for the regiospecific hydrosilation of α,β-unsaturated carbonyl compounds
作者:T.H. Chan、Guo Zhu Zheng
DOI:10.1016/s0040-4039(00)93388-4
日期:1993.5
Hydridotetrakis(triphenylphosphine)rhodium(I) acts as an effective catalyst for the reactions of alpha,beta-unsaturated carbonyl compounds with silanes to give regioselectively the enol silyl ethers in a 1,4-hydrosilation.
Hydrosilylation of enones: platinum divinyltetramethyldisiloxane complex in the preparation of triisopropylsilyl and triphenylsilyl enol ethers
作者:Carl R. Johnson、Raj K. Raheja
DOI:10.1021/jo00088a006
日期:1994.5
Enones are regioselectively converted to triisopropylsilyl and triphenylsilyl enol ethers in high yields using triisopropylsilane or triphenylsilane and platinum divinyltetramethyldisiloxane complex 1 (Karstedt's catalyst).
Johnson Carl R., Raheja Raj K., J. Org. Chem, 59 (1994) N 9, S 2287-2288