Asymmetric synthesis of oxindoles containing a quaternary stereogenic centre by catalytic O/C-carboxyl rearrangement
作者:Muhammad Ismail、Huy V. Nguyen、Gennadiy Ilyashenko、Majid Motevalli、Christopher J. Richards
DOI:10.1016/j.tetlet.2009.08.122
日期:2009.11
A catalysed O/C-carboxyl rearrangement generates the all-carbon stereogenic centre in phenyl 1,3-dimethyl-5-methoxy-2-oxoindoline-3-carboxylate (up to 57% ee). Crystallisation and removal of racemic crystals enhance the ee to 95%. The X-ray crystal structure of the cobalt metallocene–pyrrolidinopyridine nucleophilic catalyst employed is reported.
催化的O / C-羧基重排在苯基1,3-二甲基-5-甲氧基-2-氧代吲哚啉-3-羧酸酯(至多57%ee)中生成全碳立构中心。结晶和外消旋晶体的去除将ee提高到95%。报道了所使用的钴金属茂-吡咯烷基二吡啶亲核催化剂的X射线晶体结构。