Enantioselective Synthesis of Quaternary α-Aminophosphonates via Conjugate Addition of α-Nitrophosphonates to Enones
摘要:
Enantioselective Michael addition of alpha-nitrophosphonates to enones for the synthesis of alpha-aminophosphonates is reported for the first time. The reaction proceeds in good to high yields and moderate to high selectivity in the presence of a new quinine thiourea catalyst. The quaternary nitrophosphonates were conveniently transformed to cyclic quaternary alpha-aminophosphonates via in situ reduction intramolecular cyclization or Baeyer-Villiger oxidation followed by in situ reduction intramolecular cyclization.
Highly Enantioselective Michael Addition of α-Substituted Nitrophosphonates to a Vinyl Sulfone
作者:Yixin Lu、Guo-Ying Chen
DOI:10.1055/s-0033-1338434
日期:——
Organocatalytic asymmetric Michael reaction of alpha-substituted nitrophosphonates to phenyl vinyl sulfone catalyzed by cinchona alkaloid-derived tertiary amine-thioureas afforded alpha,alpha-disubstituted nitrophosphonates in very good yields and excellent enantiomeric excesses.