Oxalyl chloride → HCID 57781142, compound

Participants

Reaction Conditions

Reaction Steps

3-(3,3-Dimethyl-1-oxo-isochroman-4-yl)-3H-imidazole-4-carboxylic acid (0.538 g, 1.88 mmol) (Example 23) is dissolved in dichloromethane (4 mL) and cooled to 0° C. Oxalyl chloride (0.41 mL, 4.702 mmol) is added and the cooling bath is removed. The mixture is stirred at room temperature for 3 h. The reaction mixture is concentrated in vacuo. The residue obtained is redissolved in chloroform and N-hydroxyacetamidine (0.181 g, 2.44 mmol) is added. The reaction mixture is stirred at reflux for 72 h. The mixture is cooled to room temperature, washed with saturated solution of sodium bicarbonate and is extracted with dichloromethane. The organic phase is dried over Na2SO4 and concentrated in vacuo. The residue is purified by silica gel chromatography (hexane-ethyl acetate, 3:7) to give dimethyl-4-[5-(3-methyl-[1,2,4]oxadiazol-5-yl)-imidazol-1-yl]-isochroman-1-one as a white solid; MS (ESI) m/z 325.0 (M+H); 1H NMR (400 MHz, MeOD) δ ppm 1.26 (s, 3 H), 1.61 (s, 3 H), 2.55 (s, 3 H), 6.94 (s, 1 H), 7.56 (d, J=7.1 Hz, 1 H), 7.63 (s, 1 H), 7.72 (td, J=7.6, 1.3 Hz, 1 H), 7.80 (td, J=7.6, 1.3 Hz, 1 H), 8.01 (s, 1 H), 8.30 (dd, J=7.8, 1.3 Hz, 1 H).

Provenance & Evidence