Rhodium-Catalyzed Cross-Cyclotrimerization and Dimerization of Allenes with Alkynes.
It has been established that a cationic rhodium(I)/binap complex catalyzes the cross-cyclotrimerization of two molecules of a monosubstituted allene with one molecule of a functionalized alkyne to give 3,6-dialkylidenecyclohex-1-enes. In contrast, the reactions involving di- or trisubstituted allenes and/or unfunctionalized alkynes afforded cross-dimerization products, substituted dendralenes, through β-hydrogen elimination from the corresponding rhodacycles.
Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo, 152-8550, Japan.|Department of Applied Chemistry, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, 184-8588, Japan.
Kazuki
K
Sakashita
Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo, 152-8550, Japan.
Yu
Y
Shibata
Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo, 152-8550, Japan. ktanaka@apc.titech.ac.jp.|Department of Applied Chemistry, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, 184-8588, Japan. ktanaka@apc.titech.ac.jp.
Ken
K
Tanaka
alkynes; allenes; cyclization; dimerization; rhodium