T. Okawa, N. Osakada, S. Eguchi*
Nov 24, 1997
Citations
0
Influential Citations
14
Citations
Journal
Tetrahedron
Abstract
Abstract (2-Oxo-1,2-dihydropyridin-3-yl)-1,3,5-triazine derivatives 10 were obtained unexpectedly, in stead of pyrido[2,3-d]pyrimidine derivatives, by the intermolecular aza-Wittig reaction of methyl 2-(N-triphenylphosphoranylidene)aminonicotinate 3 with aryl isocyanates followed by attempted heterocyclization by use of prim-amines. A novel sequential aza-Wittig / cycloaddition / ring-transformation mechanism for the formation of 10 has been reported based on the isolation and characterization of the key intermediates, pyrido[1,2-a][1,3,5]triazines 15 formed via [4+2] cycloaddition of the initially produced carbodiimide with aryl isocyanates.