2,3-Diaminobenzoic acid → (S)-2-(2-(difluoromethyl)-4-((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)phenyl)-1H-benzo[d]imidazole-4-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of (S)-2-(difluoromethyl)-4-((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)benzaldehyde (66; 1.83 g, 6.40 mmol) in DMF (150 ml) was added 2,3-diaminobenzoic acid (1; 0.97 g, 6.40 mmol), and Na2S2O5 (1.82 g, 9.60 mmol). The reaction mixture was stirred at 110° C. for 18 h. It was then cooled to room temperature and diluted with water. The resulting solids were collected by filtration and dried to afford (S)-2-(2-(difluoromethyl)-4-((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)phenyl)-1H-benzo[d]imidazole-4-carboxylic acid 67 as dark yellow solid (0.84 g, 51%). MS (ESI) calcd for C21H20F2N5O5: 418.13; found: 419 [M+H].

Provenance & Evidence