boron tribromide in dichloromethane
1 h at -70 deg C, then within 2 h to room temp.;
参考文献
Murphy, William S.; Wattanasin, Sompong
Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999), 1980 , p. 1555 - 1566
