1: in dichloromethane
cooling;
2: With dibenzyl azodicarboxylate in dichloromethane
cooling;
3: With trifluoroacetic acid in dichloromethane
Further stages.;
参考文献
Sun, Weilin; Pelletier, Jeffrey C.
Tetrahedron Letters, 2007 , vol. 48, # 44 p. 7745 - 7746