ao7b00693_si_001.pdf (8.86 MB)
Synthesis of Benzo[4,5]imidazo[1,2‑c]pyrimidin-1-amines and Their Analogs via Copper-Catalyzed C–N Coupling and Cyclization
journal contribution
posted on 2017-06-26, 11:50 authored by Pham Duy
Quang Dao, Ha Kyeong Lee, Ho-Sang Sohn, Nam Sik Yoon, Chan Sik Cho2-(2-Bromovinyl)benzimidazoles
and 2-(2-bromophenyl)benzimidazoles
react with cyanamide by microwave irradiation in dimethylformamide
in the presence of a catalytic amount of CuI along with a base to
give the corresponding benzo[4,5]imidazo[1,2-c]pyrimidin-1-amines
and benzo[4,5]imidazo[1,2-c]quinazolin-6-amines,
respectively, in moderate to good yields. 2-(2-Bromophenyl)indoles
also react with cyanamide under similar conditions to afford indolo[1,2-c]quinazolin-6-amines. The reaction pathway seems to proceed
via a sequence such as intermolecular C–N coupling, C–N
formative cyclization, and tautomerization.