Sulfuric Acid → Thiocyanic acid, 4-methoxy-2-nitrophenyl ester

Participants

Reaction Conditions

Reaction Steps

A sample of 3-nitro-4-aminoanisole (13.5 g, 80 mmol) was dissolved in water (100 mL) and concentrated H2SO4 (44 mL), cooled to 0° C., and diazotized with a solution of sodium nitrite (14.3 g, 207.2 mmol) in water (25 mL) while maintaining a temperature no greater than 5° C. The resulting solution was added dropwise with vigorous stirring to a solution of crystalline cobalt chloride (42 g, 176 mmol) and potassium thiocyanate (25.6 g, 264 mmol) in water (100 mL), after which the mixture was stirred at 0-10° C. for 3 h and allowed to stand overnight. It was then stirred at 50° C. for 16 h until nitrogen evolution had ceased. The precipitate was removed by filtration, washed with water, and dried at 80° C. to give 4-methoxy-2-nitro-1-thiocyanatobenzene (intermediate 22) (9.82 g, 58%). mp: 127-128° C.

Provenance & Evidence