TY - JOUR AU - Kumar, Vikas; Ray, Bidisha; Rathi, Preeti; Mukherjee, Santanu TI - Catalytic Asymmetric Direct Vinylogous Michael Addition of γ-Aryl-Substituted Deconjugated Butenolides to Nitroolefins and N-Phenylmaleimide SN - 0039-7881 SN - 1437-210X PY - 2013 JO - Synthesis JF - Synthesis LA - EN VL - 45 IS - 12 SP - 1641 EP - 1646 ET - 2013/05/08 DA - 2013/06/05 KW - Michael reaction KW - butenolide KW - quaternary stereocenter KW - nitroolefin KW - maleimide AB - Direct asymmetric vinylogous Michael reactions of γ-aryl-substituted deconjugated butenolides with nitroolefins and N-phenylmaleimide are described using bifunctional thiourea derivatives as the catalyst. The resulting butenolide derivatives containing adjacent quaternary and tertiary stereocenters are obtained in good yields (54–90%) and with excellent enantioselectivities (er up to 99:1) and high diastereoselectivities (dr up to >20:1). PB - © Georg Thieme Verlag DO - 10.1055/s-0033-1338705 UR - http://www.thieme-connect.com/products/ejournals/abstract/10.1055/s-0033-1338705 ER -