Asymmetric cyclization of 2-butenylene dicarbamates catalyzed by chiral ferrocenylphosphine-palladium complexes: Catalytic asymmetric synthesis of optically active 2-amino-3-butenols
作者:Tamio Hayashi、Akihiro Yamamoto、Yoshihiko Ito
DOI:10.1016/0040-4039(88)80027-3
日期:1988.1
Cyclization of 2-butenylenedicarbamates (RNHCOOCH2CH=CHCH2OCONHR: R = Ph, MeOC6H4, PhCHCH, etc.) in the presence of a palladium catalyst coordinated with chiral (hydroxyalkyl)-ferrocenylphosphine ligand gave opticallyactive 4-vinyl-2-oxazolidones (up to 77% ee) in high yields, which were hydrolyzed to opticallyactive2-amino-3-butenols.
substituted N-aryl-2-cyanoazetidines based on an anionic ring-closure reaction. These compounds can be prepared from β-amino alcohols in enantiomerically pure form through a three-step sequence involving (i) copper-catalyzed N-arylation, (ii) N-cyanomethylation of the secondary aniline, and (iii) one-pot mesylation followed by ring closure induced by a base. This high-yielding sequence gives access to azetidines