Ethyl (4-bromo-2-cyanophenyl)carbamate

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

Procedure: As described for example 1a) (4-bromo-2-cyano-phenyl)-carbamic acid ethyl ester (19.9 g, 74.2 mmol) instead of (4-chloro-2-cyano-phenyl)-carbamic acid ethyl ester using methoxymethyl-carboxylic acid hydrazide instead of cyclopropane-carboxylic acid hydrazide, was converted to the title compound (21.1 g, 92%) which was obtained as a light yellow solid. MS: m/e=308.9/310.9 [M+H]+.

Conditions: temp:160.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of (4-bromo-2-cyano-phenyl)-carbamic acid ethyl ester (40.4 g, 150 mmol) in NMP (170 mL) was added formylhydrazine (10.0 g, 150 mmol). The resulting mixture was stirred for 1.5 h at 160° C. under a gentle nitrogen sweep. It was cooled to below 100° C. and water (340 mL) was added slowly. The resulting slurry was cooled to 25° C. and stirred for 15 min. The solid was collected by filtration and washed with water and 2-propanol. Drying in vacuo afforded the title compound (32.4 g, 81%) as a light yellow solid. MS: m/e 264.9/267.0 [M+H+]. It was cooled to below 100° C. The resulting slurry was cooled to 25° C. stirred for 15 min The solid was collected by filtration washed with water and 2-propanol Drying in vacuo

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

Procedure: A suspension of 2-amino-5-bromobenzonitrile (58.5 g, 297 mmol) in ethyl chloroformate (141 mL, 1.48 mol) was heated at reflux for 5 h. The excess ethyl chloroformate (99 mL) was distilled off and toluene (96 mL) was added. Slow addition of cyclohexane (228 mL) induced crystallization. The resulting solid was collected by filtration and rinsed with cyclohexane. Drying in vacuo afforded the title compound (54.3 g, 68%) as an orange solid. MS: m/e=267.1/269.2 [M—H−]. was heated at reflux for 5 h The excess ethyl chloroformate (99 mL) was distilled off toluene (96 mL) was added Slow addition of cyclohexane (228 mL) crystallization The resulting solid was collected by filtration rinsed with cyclohexane Drying in vacuo