Direct conversion of chiral cyanohydrins to chiral nitrones by transimination
摘要:
A new method for the preparation of enantiomerically pure N-benzyl nitrones is described. By using either a one-pot reduction-transimination or a one-pot Grignard addition-transimination sequence chiral O-protected alpha-hydroxynitriles can be converted into chiral aldo- and ketonitrones, respectively. (C) 1997 Elsevier Science Ltd.
Enantiomerically pure tetrahydroisoquinolines by enzyme catalysis and gold-catalyzed phenol synthesis
作者:A. Stephen K. Hashmi、Filiz Ata、Patrick Haufe、Frank Rominger
DOI:10.1016/j.tet.2008.12.058
日期:2009.2
Five different furfural derivatives were converted to chiral cyanohydrins by enzyme catalysis in good enantiomeric excess. After a sequence of silyl protection, nitrile reduction, tosylation and propargylation, substrates for the gold(I) catalyzed cycloisomerization of δ-alkynyl furans delivered good yields of enantiomerically pure dihydroxytetrahydroisoquinoline building blocks. Neither racemization
Direct conversion of chiral cyanohydrins to chiral nitrones by transimination
作者:Edith Hulsbos、Jan Marcus、Johannes Brussee、Arne van der Gen
DOI:10.1016/s0957-4166(97)00066-9
日期:1997.4
A new method for the preparation of enantiomerically pure N-benzyl nitrones is described. By using either a one-pot reduction-transimination or a one-pot Grignard addition-transimination sequence chiral O-protected alpha-hydroxynitriles can be converted into chiral aldo- and ketonitrones, respectively. (C) 1997 Elsevier Science Ltd.