15620-34-5Relevant articles and documents
Highly effective and enantioselective Michael addition of 4-hydroxycoumarin to α,β-unsaturated ketones promoted by simple chiral primary amine thiourea bifunctional catalysts
Mei, Ren-Qiang,Xu, Xiao-Ying,Li, Yan-Chun,Fu, Ji-Ya,Huang, Qing-Chun,Wang, Li-Xin
supporting information; experimental part, p. 1566 - 1568 (2011/05/05)
Highly asymmetric Michael addition of 4-hydroxycoumarin to α,β-unsaturated ketones promoted by chiral primary amine thiourea bifunctional catalysts was developed and a series of Michael adducts were obtained in excellent yields (up to 97%) and enantioselectivities (up to 95% ee). Optically pure S-warfarin was easily obtained in 99% ee after single recrystallization.
Organocatalytic Asymmetric Michael Reaction of Cyclic 1,3-Dicarbonyl Compounds and α,β-Unsaturated Ketones - A Highly Atom-Economic Catalytic One-Step Formation of Optically Active Warfarin Anticoagulant
Halland, Nis,Hansen, Tore,Jorgensen, Karl Anker
, p. 4955 - 4957 (2007/10/03)
A broad range of Michael adducts 3 were obtained by the organocatalytic asymmetric Michael addition of cyclic 1,3-dicarbonyl compounds 1 to α,β-unsaturated ketones 2. The reaction allows a one-step synthesis of the optically active anti-coagulant warfarin and several analogues 3 on a kilogram scale in up to 99% yield with 88% ee (>99.9% ee after a single recrystallization).
