Synthesis of indolizinones
A highly efficient catalyst-free, thermally induced cycloisomerization allows the synthesis of indolizinones from readily available tertiary propargylic alcohols. In addition, this transformation was found to be further expedited by microwave irradiation.
I. Kim, J. Choi, S. Lee, G. H. Lee, Synlett, 2008, 2334-2338.
A copper-catalyzed cycloisomerization of 2-pyridyl-substituted propargylic acetates and its derivatives offers an efficient route to C-1 oxygenated indolizines with a wide range of substituents under mild reaction conditions. The presented method could be readily applied to the synthesis of indolizinones through a cyclization/1,2-migration of tertiary propargylic alcohols.
B. Yan, Y. Zhou, H. Zhang, J. Chen, Y. Liu, J. Org. Chem., 2007, 72, 7783-7786.
A palladium-catalyzed domino process involving aminopalladation, reductive elimination, and 1,2-shift enables a direct one-pot approach to polysubstituted indolizinones from tertiary propargylic alcohols.
I. Kim, K. Kim, Org. Lett., 2010, 12, 2500-2503.