Catalytic Asymmetric Claisen Rearrangement of Unactivated Allyl Vinyl Ethers
作者:Maryll E. Geherty、Robert D. Dura、Scott G. Nelson
DOI:10.1021/ja1039314
日期:2010.9.1
original discovery, catalyzed enantioselective variants of the venerable Claisenrearrangement remain relatively rare. We have discovered a cooperative transition metal-Lewis acid cocatalyst system that affects highly enantio- and diastereoselective examples of archetypical Claisenrearrangements. The catalyzed rearrangements proceed using an easily prepared enantioenriched transition metal catalyst
Stereodivergent α-Allylation of Linear Aldehydes with Dual Iridium and Amine Catalysis
作者:Simon Krautwald、Michael A. Schafroth、David Sarlah、Erick M. Carreira
DOI:10.1021/ja5003247
日期:2014.2.26
linear aldehydes. The reaction proceeds via direct iridium-catalyzedsubstitution of racemic allylic alcohols with enamines generated in situ. The use of an Ir(P,olefin) complex and a diarylsilyl prolinol ether as catalysts in the presence of dimethylhydrogen phosphate as the promoter proved to be crucial for achieving high enantio- and diastereoselectivity (>99% ee, up to >20:1 dr). The utility of the