Takenori Nishino, Masumi Kiyokawa, Yoshiyuki Miichi
Apr 1, 1972
Citations
0
Influential Citations
7
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
The reaction of 2-dimethoxymethyl-3-methoxypropionitrile (1) with acetamidine yields 2,7-dimethyl-5,6-dihydropyrimido[4,5-d]pyrimidine (6) via an intermediate, λmaxMeOH 262 mμ. This intermediate has been identified as 2-acetamidinomethylene-3-methoxypropionitrile (5) without being isolated. However, this assignment seems to be somewhat inconsistent with the stabilities of an acetal group in basic media and with the UV spectra of compounds with structures similar to 5. The reaction of 1 with sodium methoxide gave a dimeric compound (8). This result suggests the formation of 2-dimethoxymethylacrylonitrile (2) in the initial stage of the reaction of 1 with acetamidine. The reaction of acrylonitrlie with acetamidine yielded 2-methyl-4-amino-5,6-dihydropyrimidine (23), whose UV spectrum in methanol showed its absorption maximum at 270 mμ in neutral media and at 258 mμ in basic media. Therefore, the structure of the intermediate may be concluded to be 2-methyl-4-amino-5-dimethoxymethyl-5,6-dihydropyrimidine (27...