Efficient highly selective synthesis of methyl 2-(ethynyl)alk-2(E)-enoates and 2-(1'-chlorovinyl)alk-2(Z)-enoates from 2-(methoxycarbonyl)-2,3-allenols.
Highly regio- and stereoselective reactions of readily available 2-(methoxycarbonyl)-2,3-allenols 1 with oxalyl chloride in the presence of Et(3)N or DMSO afforded methyl 2-(ethynyl)alk-2(E)-enoates (E)-2 and 2-(1'-chlorovinyl)alk-2(Z)-enoates (Z)-3, respectively, in moderate to good yields.
Laboratory of Molecular Recognition and Synthesis, Department of Chemistry, Zhejiang University, Hangzhou 310027, Zhejiang, People's Republic of China.
Youqian
Y
Deng
Xin
X
Jin
Chunling
C
Fu
Shengming
S
Ma