SIMPLE SYNTHESIS OF TRANS-ALPHA,BETA-DIBENZYL-GAMMA-BUTYROLACTONE LIGNANS BY DIASTEREOSELECTIVE REDUCTION OF ALPHA-BENZYLIDENE-BETA-BENZYL-GAMMA-BUTYROLACTONES USING NABH4-NICL2

Authors
MORITANI Y FUKUSHIMA C MIYAGISHIMA T OHMIZU H IWASAKI T
Citation
Y. Moritani et al., SIMPLE SYNTHESIS OF TRANS-ALPHA,BETA-DIBENZYL-GAMMA-BUTYROLACTONE LIGNANS BY DIASTEREOSELECTIVE REDUCTION OF ALPHA-BENZYLIDENE-BETA-BENZYL-GAMMA-BUTYROLACTONES USING NABH4-NICL2, Bulletin of the Chemical Society of Japan, 69(8), 1996, pp. 2281-2286
Citations number
46
Categorie Soggetti
Chemistry
Journal title
Bulletin of the Chemical Society of Japan → ACNP
ISSN journal
00092673
Volume
69
Issue
8
Year of publication
1996
Pages
2281 - 2286
Database
ISI
SICI code
0009-2673(1996)69:8<2281:SSOTL>2.0.ZU;2-M
Abstract
trans-alpha,beta-Dibenzyl-gamma-butyrolactone lignans were synthesized by stereoselective reduction of alpha-benzylidene-beta-benzyl-gamma-b utyrolactones using NaBH4-NiCl2. The reduction is found to proceed via conjugate addition of a hydride to an alpha-benzylidene-beta-benzyl-g amma-butyrolactone and the stereoselective protonation of the resultin g metal enolate. The stereoselectivity would be brought about by the c onformational rigidity of the phenyl moiety of the cr-benzyl group ind uced by 1,3-allylic strain.