Sequential Michael Addition and Enamine-Promoted Inverse Electron Demanding Diels-Alder Reaction upon 3-Vinyl-1,2,4-triazine Platforms

An original one-pot Michael addition-ihDA/rDA sequence was achieved from 3-vinyl-1,2,4-triazine platforms used as unprecedented Michael acceptors. This sequence provides a novel access to functionalized [2,3]-fused pyridine derivatives via a unique enamine promoted intramolecular ihDA reaction of 1,2,4-triazine intermediates.