(5-bromo-2-chlorophenyl)hydrazine;hydrochloride

Conditions: temp:5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A suspension of 5-bromo-2-chloroaniline (23 g, 0.11 mol) in concentrated hydrochloric acid (150 mL) and water (90 mL) was cooled in an ice/salt bath. A solution of sodium nitrite (8 g, 0.11 mol) in water (50 mL) was added dropwise to the reaction mixture while maintaining the temperature below 4° C. After stirring for 30 minutes the suspension was transferred via cannula to a solution of SnCl2 dihydrate in concentrated hydrochloric acid (170 mL) and cooled to 5° C. The resulting thick suspension was stirred for 2 h at 5° C. and the solid was isolated via filtration. The solid was air dried and then further dried by adding chlorobutane (500 mL) and refluxing using a Dean-Stark condenser. After cooling, the solid was isolated by filtration to afford the title compound as an off-white solid (35.3 g). was cooled in an ice/salt bath while maintaining the temperature below 4° C The resulting thick suspension was stirred for 2 h at 5° C. the solid was isolated via filtration dried further dried by adding chlorobutane (500 mL) refluxing After cooling the solid was isolated by filtration

Conditions: temp:5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A suspension of 5-bromo-2-chloroaniline (23 g, 0.11 mol) in concentrated hydrochloric acid (150 mL) and water (90 mL) was cooled in an ice/salt bath. A solution of sodium nitrite (8 g, 0.11 mol) in water (50 mL) was added dropwise to the reaction mixture while maintaining the temperature below 4° C. After stirring for 30 minutes the suspension was transferred via cannula to a solution of SnCl2 dihydrate in concentrated hydrochloric acid (170 mL) and cooled to 5° C. The resulting thick suspension was stirred for 2 h at 5° C. and the solid was isolated via filtration. The solid was air dried and then further dried by adding chlorobutane (500 mL) and refluxing using a Dean-Stark condenser. After cooling, the solid was isolated by filtration to afford the title compound as an off-white solid (35.3 g). 1H NMR (CD3COCD3): δ 10.25 (br s, 1H), 8.32 (br s, 2H) 7.38 (d, 1H), 7.30 (d, 1H), 7.16 (dd, 1H). was cooled in an ice/salt bath while maintaining the temperature below 4° C The resulting thick suspension was stirred for 2 h at 5° C. the solid was isolated via filtration dried further dried by adding chlorobutane (500 mL) refluxing After cooling the solid was isolated by filtration