alpha-Hypervalent iodine functionalized phosphonium and arsonium ylides and their tandem reaction as umpolung reagents.
alpha-Hypervalent iodine functionalized phosphonium and arsonium ylides 2 can be used as umpolung ylides to react with nucleophiles to give alpha-heteroatom substituted ylides 4 in good yields. The nucleophilic substitution-Wittig tandem reaction of 2 can occur smoothly to provide an efficient method for the synthesis of (Z)-alpha-halo-alpha,beta-unsaturated enoates or enones 6, stereoselectively.
Huang
Zhizhen
Z
Department of Chemistry, Zhejiang University, Xixi Campus, Hangzhou 310028, P. R. China.
Yu
Xiaochun
X
Huang
Xian
X