Guanidine Hydrochloride → HCID 178513102, compound

Participants

Reaction Steps

A solution of tert-butyl(2-benzoyl-5-phenyl-1H-pyrrol-1-yl)acetate (148 mg, 0.41 mmol) in trifluoroacetic acid was stirred for 2 h at room temperature. After removal of trifluoroacetic acid, the residue was treated with CH2Cl2 (10 ml), MeOH (1 ml) and H2O (10 ml). The two layers were separated and the aqueous was extracted with CH2Cl2 (3×10 ml). The combined organic extracts were washed with H2O (10 ml), brine (10 ml), dried (Na2SO4) filtered and concentrated. The crude material was purified by chromatography (silica gel, EtOAc/hexane/HCO2H: 10/40/0.1) to afford (2-benzoyl-5-phenyl-1H-pyrrol-1-yl)acetic acid (125 mg, 100%) as an oil. To a stirred solution of (2-benzoyl-5-phenyl-1H-pyrrol-1-yl)acetic acid (260 mg, 0.85 mmol) in DMF (2.0 ml) was added 1,1′-carbonyldiimidazole (166 mg, 1.02 mmol) at room temperature. After stirring for 1 h, the reaction mixture was treated with a solution of guanidine hydrochloride (244 mg, 2.55 mmol) in DMF (2.5 ml) and triethylamine (0.54 ml, 2.55 mmol). After stirring over night, the reaction mixture was quenched with H2O (30 ml). The aqueous was extracted with Et2O (3×30 ml), EtOAc (10 ml). The combined organic extracts were dried (Na2SO4), filtered and concentrated. The crude material was purified by chromatography (silica gel; EtOAc/hexane/2M NH3 in MeOH: 65/35/1) to give the titled compound (169 mg, 58%) as a white solid: mp 201-203° C.; MS (−) ES, 345 (M−H)−.

Provenance & Evidence