Synthesis and characterisation of severely hindered P-OR compounds
作者:D. Bradley G. Williams、Takelani E. Netshiozwi
DOI:10.1016/j.tet.2009.10.008
日期:2009.11
P-Cl substrates were converted into their P-OR analogues from hindered alcohols using an amine base. Where the system was severely hindered, more forcing conditions were required that necessitated the presence of a metal alkoxide nucleophile before successful reactions were observed. In some instances, the products were thermally unstable and reverted to alkenes by elimination reactions, while others were sensitive to moisture. Here, hydrolysis products prevailed if moisture was not rigorously excluded. Details are presented to obtain the P(III) and P(V) esters, diesters and half esters. (C) 2009 Elsevier Ltd. All rights reserved.
Asymmetric hydrogenation of enol phosphinates catalyzed by a chiral ferrocenylphosphine-rhodium complex. Asymmetric synthesis of optically active secondary alkyl alcohols
作者:Tarnio Hayashi、Koichi Kanehira、Makoto Kumada
DOI:10.1016/s0040-4039(01)82972-5
日期:1981.1
Catalyticasymmetricsynthesis of secondary alkyl alcohols (up to 78% ee) was accomplished by asymmetric hydrogenation of enol diphenylphosphinates, derived from prochiral ketones such as acetophenone, 3-methyl-2-butanone, and 2-octanone, in the presence of a cationic rhodium complex of (R)-1-[(C)-1′,2-bis(diphenylphosphino)ferrocenyl]ethanol (BPPFOH).