Enantioselective N‐Heterocyclic Carbene Catalysis that Exploits Imine Umpolung
作者:Jared E. M. Fernando、Yuji Nakano、Changhe Zhang、David W. Lupton
DOI:10.1002/anie.201812585
日期:2019.3.18
to reaction discovery. Herein we report an enantioselective aza‐Stetter reaction that proceeds via imine umpolung using N‐heterocyclic carbene catalysis. The reaction proceeds with high levels of enantioselectivity (all ≥96:4 er) and good generality (21 examples). Mechanistic studies are reported and are consistent with turnover‐limiting addition of the NHC to the imine.
α-Aryloxymethylacrylic acids and their derivatives have been found to undergo some novel thermal transformations leading to the formation of ‘ene’ dimers. The structure of the dimer has been revised on the basis of degradation studies, extensive spectral data and isolation of intermediates.