Cationic rhodium(I) complex-catalyzed [3 + 2] and [2 + 1] cycloadditions of propargyl esters with electron-deficient alkynes and alkenes.
A cationic rhodium(I) complex, [Rh(cod)(2)]SbF(6), catalyzes the [3 + 2] cycloaddition of propargyl esters with dialkyl acetylenedicarboxylates in good yields, presumably through carbonyl-stabilized cationic rhodium(I) alkenylcarbene intermediates. The same rhodium(I) complex also catalyzes the [2 + 1] cycloaddition (cyclopropanation) of propargyl esters with N,N-disubstituted acrylamides in good yields with perfect diastereoselectivity.
Shibata
Yu
Y
Department of Applied Chemistry, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan.
Noguchi
Keiichi
K
Tanaka
Ken
K