Abstract Novel dihydropyrido [3, 2-ij] quinazoline cobalt complexes were synthesized from the cocyclization reaction of 1-alkynyl pyrimidines with disubstituted alkynes. The chemo-, regio-, and stereoselective participation of pyrimidine derivatives in cobalt-mediated [2+ 2+ 2] cycloaddition reactions were investigated as a new synthetic entry to modified nucleosides.
