Copper-catalyzed α-selective hydrostannylation of alkynes for the synthesis of branched alkenylstannanes
作者:H. Yoshida、A. Shinke、Y. Kawano、K. Takaki
DOI:10.1039/c5cc02720a
日期:——
A universal system for highly α-selective hydrostannylation of terminal alkynes has been developed by use of a distannane or a silylstannane as a stannylating reagent under copper catalysis.
The reaction of terminal acetylenes with Bu3SnMgMe, Bu3SnA1Et2, or (Bu3Sn)2Zn in the presence of various transition-metal catalysts provides vinylstannanes in good yields. Whereas copper catalysed stannylmagnesation of 4-benzyloxy-1-butyne gives (E)-4-benzyloxy-1-tributylstannyl-1-butene exclusively, palladium catalysed stannylzincation affords 4-benzyloxy-2-tributylstannyl-1-butene preferentially