Squaramide-Catalyzed Enantioselective Michael Addition of Masked Acyl Cyanides to Substituted Enones
作者:Kin S. Yang、Antoinette E. Nibbs、Yunus E. Türkmen、Viresh H. Rawal
DOI:10.1021/ja409012q
日期:2013.10.30
Masked acyl cyanide (MAC) reagents are shown to be effective umpolung synthons for enantioselective Michaeladdition to substituted enones. The reactions are catalyzed by chiral squaramides and afford adducts in high yields (90–99%) and with excellent enantioselectivities (85–98%). The addition products are unmasked to produce dicyanohydrins that, upon treatment with a variety of nucleophiles, provide
Restoration of catalytic activity by the preservation of ligand structure: Cu-catalysed asymmetric conjugate addition with 1,1-diborylmethane
作者:Changhee Kim、Byeongdo Roh、Hong Geun Lee
DOI:10.1039/d0sc06543a
日期:——
conditions that control the amount of nucleophilic alkoxide base, which is the origin of ligand decomposition. Overall, the strategy has been successfully applied to a new class of asymmetric conjugate addition reactions with bis[(pinacolato)boryl]methane, in which α,β-unsaturated enones are utilised as substrates.