Triazolo[4, 5-d]pyrimidines. XII. Reaction of 6-Benzoyl-6, 7-dihydro-3-phenyl-3H-1, 2, 3-triazolo-[4, 5-d]pyrimidines (Triazolopyrimidine Reissert Compounds) with Acid, Base, and Electrophile

抄録

In the treatment of 6-benzoyl-6, 7-dihydro-3-phenyl-3H-1, 2, 3-triazolo[4, 5-d]pyrimidine-7-carbonitrile (1, triazolo-pyrimidine Reissert compound) and 6-benzoyl-6, 7-dihydro-5-methyl-3-phenyl-3H-1, 2, 3-triazolo[4, 5-d]pyrimidine-7-carbonitrile (2, 5-methyltriazolopyrimidine Reissert compound) with an acid, the ring fission of the pyrimidine ring proceeded to give the triazole derivatives (3-7). Alkaline hydrolysis of 2 and 1 gave 5-metyl-3-phenyl- (10) and 3-phenyl-3H-1, 2, 3-triazolo[4, 5-d]pyrimidines (9), respectively. The anions, generated from 1 and 2 with sodium hydride (NaH), underwent aromatization to give the 3H-1, 2, 3-triazolo[4, 5-d]pyrimidine-7-carbonitriles (12 and 14). Compounds 1 and 2 reacted with arylaldehydes in the presence of NaH to give corresponding 3H-1, 2, 3-triazolo[4, 5-d]pyrimidin-7-ylmethyl benzoates (15 and 17).