Rhodium-Catalyzed Chemo- and Regioselective Intermolecular Cross-Cyclotrimerization of Nonactivated Terminal and Internal Alkynes
![Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F51444.jpg&w=3840&q=50)
Shuhei Nishigaki1, Yu Shibata1, Ken Tanaka1
1Department of Chemical Science and Engineering, Tokyo Institute of Technology , O-okayama, Meguro-ku, Tokyo 152-8550, Japan.
Abstract:
It has been established that a cationic rhodium(I)/BIPHEP complex is able to catalyze the unprecedented intermolecular cross-cyclotrimerization of nonactivated terminal and internal alkynes at room temperature. In this transformation, the use of arylacetylenes as terminal alkynes and 1,4-butynediol derivatives as internal alkynes afforded the cross-cyclotrimerization products with good chemo- and regioselectivity. The present study clearly demonstrated that an electronically biased combination of nonactivated and electron-deficient alkynes is not necessary to realize good chemo- and regioselectivity in the cationic rhodium(I) complex-catalyzed intermolecular cross-cyclotrimerization.
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