Catalyst-Free Annulation of 2-Pyridylacetates and Ynals with Molecular Oxygen: An Access to 3-Acylated Indolizines
摘要:
A catalyst and additive-free annulation of 2-pyridylacetates and ynals under molecular oxygen was the first developed, affording 3-acylated indolizines in good to excellent yields. Molecular oxygen was used as the source of the carbonyl oxygen atom in indolizines. This approach was compatible with a wide range of functional groups, and especially it has been successfully extended to unsaturated double bonds and triple bonds, which were difficult to prepare by previous methods in a single step.
Facile approach to diverse 3-acylated indolizines via a sequential Sonogashira coupling/iodocyclization process
作者:Youngeun Jung、Ikyon Kim
DOI:10.1016/j.tet.2012.07.068
日期:2012.9
Successful implementation of a sequential Pd-catalyzed Sonogashira cross-coupling/iodine-promoted 5-exo-dig cyclization procedure with pyridines bearing a terminalalkyne moiety provided direct and straightforward access to a diverse array of 3-acylated indolizines under mild conditions.