Convenient Preparations of Diethyl phosphonates, 2-Azabutadienes, and Isoquinolines from a 1,2-Monoazabisylide Equivalent

Article abstract of DOI:10.1021/jo00095a035

Diethyl <(triphenylphosphoranylidene)amino>methyl>phosphonate (4), prepared in situ by treatment of 1-<<(triphenylphosphoranylidene)amino>methyl>benzotriazole (betmip 6) with diethyl phosphite anion, is converted by treatment with butyllithium into the corresponding carbanion 5.Carbanion 5, the first example of a 1,2-monoazabisylide equivalent, provides a versatile synthetic method to introduce the C=NC=C structural unit, as illustrated by convenient preparations of 1,4-diaryl-2-azabutadienes, 1,1,4,4-tetraaryl-2-azabutadienes, diethyl <(acylamino)methyl>phosphonates, and isoquinolines.