A Designer Axially Chiral Amino Sulfonamide as an Efficient Organocatalyst for Direct Asymmetric<i>anti</i>-Selective Mannich Reactions and<i>syn</i>-Selective Cross-Aldol Reactions
作者:Taichi Kano、Yukako Yamaguchi、Keiji Maruoka
DOI:10.1002/chem.200900267
日期:2009.7.6
Amino sulfonamide catalyst: A distal proton of the axially chiral amino sulfonamide (S)‐1 realized the opposite diastereoselectivity in Mannich and cross‐aldol reactions compared with that observed in proline‐catalyzed reactions. The reactions catalyzed by (S)‐1 proceeded smoothly to give the anti‐Mannich and syn‐aldol adducts in excellent enantioselectivity (see scheme).
氨基磺酰胺催化剂:与脯氨酸催化反应相比,轴向手性氨基磺酰胺(S)-1的远端质子在曼尼希和交叉羟醛反应中实现了相反的非对映选择性。由(S)-1催化的反应进行得很顺利,从而得到了具有出色对映选择性的抗曼尼希和顺式醇醛加合物(参见方案)。