The diastereospecific aprotic conjugate addition reactions of carbanions derived from allylic sulfoxides and allylic phosphine oxides.
作者:Malcolm R. Binns、Richard K. Haynes、Andrew A. Katsifis、Paul A. Schober、Simone C. Vonwiller
DOI:10.1016/s0040-4039(00)98553-8
日期:——
The title carbanions undergo conjugate addition to cyclic enones in THF to deliver vinylic sulfoxides and vinylic phosphineoxides as single diastereomers.
Reaction of dialkyl- or diaryl-trans-(3,4-epoxycyclopentyl)phosphine oxides 2 with the lithium derivative of methyldiphenylphosphine oxide gives a mixture of (+/-)-t-4- and (+/-)-c-4-(disubstituted phosphinoyl)-t-2-(diphenylphosphinoyl-methyl)-r-1-cyclopentanol derivatives 13a-c and 16a-c, which could be obtained in pure form by separation of the corresponding acetates 14a-c and 17a-c followed by methanolysis. Compounds 13b and 16b were transformed into the corresponding dehydroxy derivatives 19 and 21 through the Barton procedure. Additionally, 16a was transformed into a diastereomeric mixture of carbamates 22 and 23 on reaction with (S)-alpha-phenylethylisocyanate which could be separated by repeated crystallization. The relative configuration of compounds 13b, 17a, 21 and 22 was established by X-ray diffraction analysis. (C) 2002 Elsevier Science Ltd. All rights reserved.
HAYNES, RICHARD K.;KATSIFIS, ANDREW G.;VONVILLER, SIMONE C.;HAMBLEY, TREV+, J. AMER. CHEM. SOC., 110,(1988) N 16, C. 5423-5433
作者:HAYNES, RICHARD K.、KATSIFIS, ANDREW G.、VONVILLER, SIMONE C.、HAMBLEY, TREV+