2-Methylbenzenesulfonic acid → HCID 178469953, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of methyl 1-amino-4-fluoro-1H-pyrrole-2-carboxylate (0.980 g, 6.20 mmol), (E)-ethyl 3-ethoxyacrylate (1.25 g, 8.68 mmol) and toluenesulfonic acid (0.059 g, 0.310 mmol) in ethanol (15 mL) was heated at 85° C. for 2 h then at reflux (100° C. bath) for an additional 2 h. The mixture was cooled and concentrated to remove the ethanol/water and additional ethanol was added and reconcentrated. The process was repeated until all of the water had been removed then residue was dissolved in ethanol (15 mL) and sodium tert-butoxide (1.190 g, 12.39 mmol) was added to make orange clear solution. This mixture was heated at 85° C. for 1 h, then cooled and concentrated to remove the ethanol and the reaction mixture was neutralized with HCl in dioxane (0.5 mL of 4N solution) then concentrated to afford a tan semi solid. This material was slurried in water and stirred for 1 h and the resulting solid was collected and rinsed with water and filtered and dried to afford the title compound (740 mg, 3.30 mmol, 53.3% yield) as a light yellow solid. HPLC (condition B): retention time=3.57 min. LCMS (condition B): m/z 224.9 +ve.

Provenance & Evidence