Water → 10-Oxo-10,11-dihydro-dibenzo[b,f]azepine-5-carboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A mixture of [2-(methoxycarbonyl-phenyl-amino)-phenyl]-acetic acid (16 g, 55.5 mmol) and polyphosphoric acid (29 g, 167 mmol in terms of P2O5) is heated to 100° C. for 4 hours. To the reaction mixture, water (41 ml) is added dropwise at 85–100° C. with stirring and cooling. At 65° C. toluene (41 ml) is added and the mixture is stirred for 30 min. The two phases are separated and washed. The organic phases are concentrated and allowed to crystallize at 0° C. to yield 12 g of pure title compound (80%).

Provenance & Evidence