methyl 2-(4-chloroanilino)-2-oxoacetate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: With stirring, 6.7 g of monomethyl oxalate chloride are added dropwise at 0° to 5° C. to a solution of 6.4 g of 4-chloroaniline and 7.9 g pyridine in 150 ml of dry methylene chloride. When the addition is complete, the suspension is stirred for 30 minutes at room temperature, then diluted with 100 ml of methylene chloride, washed twice with 3N hydrochloric acid and once with saturated sodium bicarbonate solution, dried and concentrated. The residual oil crystallises on trituration, affording 10.4 g of crystalline title compound with a melting point of 162°-164° C. When the addition the suspension is stirred for 30 minutes at room temperature washed twice with 3N hydrochloric acid and once with saturated sodium bicarbonate solution dried concentrated The residual oil crystallises on trituration