Rh-catalyzed enantioselective [2 + 2] cycloaddition of alkynyl esters and norbornene derivatives.
[reaction: see text] The enantioselective [2 + 2] cycloaddition of alkynes possessing an ester functionality and norbornene derivatives proceeded efficiently using a chiral rhodium catalyst. The chiral tri- and tetracyclic cyclobutenes were obtained in moderate to high ee.
Department of Chemistry, School of Science and Engineering, Waseda University, Shinjuku, Tokyo 169-8555, Japan. tshibata@waseda.jp
Takanori
T
Shibata
Kyoko
K
Takami
Ai
A
Kawachi