Ethyl orthoformate → 2-[(S)-1-Phenylethylamino]-4-[5-(tetrazol-1-yl)-benzimidazol-1-yl]pyrimidine

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-[(S)-1-phenylethylamino]-4-[5-aminobenzimidazol-1-yl]pyrimidine (EXAMPLE 79) (80 mg) in acetic acid (2 mL) was added triethyl orthoformate (123 μL). The reaction was stirred at room temperature for 1 h, at 75° C. for 2 h, and then at room temperature again overnight (≈14 h). NaN3 (47 mg, 3 eq.) was added; the reaction was stirred at 75° C. for 5 h. The reaction was cooled, quenched with water, extracted with methylene chloride. The organic solution was washed with water and brine; it was dried over Na2SO4. Removal of the solvent and subsequent purification by preparative thin layer chromatography (acetone:hexane=1:1) provided the title compound (20 mg). Mass spectrum (ESI): 384 (M+1). 1H NMR (500 MHz, CDCl3): δ 9.04 (s, 1H); 8.56 (br s, 1H); 8.46 (d, J=5.2 Hz, 1H); 8.08 (s, 1H); 7.82 (br s, 1H); 7.57 (br s, 1H); 7.50-7.25 (m, 5H); 6.79 (d, J=5.3 Hz, 1H); 5.88 (br s, 1H); 5.18 (br s, 1H); 1.67 (d, J=6.8 Hz, 3H).

Provenance & Evidence