Efficient general asymmetric syntheses of 3-substituted 1(3H)-isobenzofuranones in very high enantiomeric excess
作者:P.Veeraraghavan Ramachandran、Guang-Ming Chen、Herbert C. Brown
DOI:10.1016/0040-4039(96)00260-2
日期:1996.3
intermolecular asymmetric reduction of methyl o-(1-oxoalkyl)benzoates with B-chlorodiisopinocampheylborane provides, after workup, 3-alkylphthalides in ≥97% ee. Unfortunately, this procedure is not as efficient for the preparation of 3-arylphthalides. However, an intramolecular reduction of B-(o-benzoylbenzoyloxy)diisopinocampheylborane, readily prepared by the treatment of o-benzoyl benzoic acid with diisopinocampheylborane
用B-氯二异opinocampheylborane在分子间不对称还原邻-(1-氧代烷基)苯甲酸甲酯,可提供≥97%ee的3-烷基邻苯二甲酸酯。不幸的是,该方法对于制备3-芳基邻苯二甲酸酯不是那么有效。然而,通过用二异松香樟基硼烷处理邻苯甲酰基苯甲酸容易制备的B-(邻苯甲酰基苯甲酰氧基)二异松香樟脑硼烷的分子内还原提供了≥96%ee的3-苯基邻苯二甲酰亚胺。