Indium(III) chloride-promoted intramolecular addition of allylstannanes to alkynes.
In the presence of an equimolar amount of InCl(3), 8-tributylstannyl-6-octen-1-ynes (allylstannanes bearing an alkynyl group) were efficiently cyclized to 2-allyl-1-methylenecyclopentanes. In contrast, catalytic use of InCl(3) gave 2-allyl-1-(tributylstannylmethylene)cyclopentanes mainly by intramolecular allylstannylation. These cyclizations could proceed via intramolecular addition of an allylindium intermediate.
Miura
Katsukiyo
K
Department of Chemistry, 21st Century COE, Graduate School of Pure and Applied Sciences, University of Tsukuba, and CREST, Japan Science and Technology Corporation (JST), Tsukuba, Ibaraki 305-8571, Japan. miura@chem.tsukuba.ac.jp
Fujisawa
Naoki
N
Hosomi
Akira
A