反应详情

A solution of 90 g (0.5 mole) of 2-amino-3-cyano-4-tert.-butyl-thiophene in 300 ml of chlorobenzene was added dropwise to a solution of 150 g of phosgene in 1.5 liters of chlorobenzene at 0°-5° C. Thereafter, the mixture was slowly heated to the boil, while passing further phosgene in, and excess phosgene was then driven off by passing dry nitrogen in. For working up, the solvent was stripped off under reduced pressure and the residue was distilled. 62 g of 3-cyano-4-tert.-butyl-thien-2-yl isocyanate, which boiled at 163° C. under a pressure of 20 mm Hg, were obtained in this manner.

1. temperatureThereafter, the mixture was slowly heated to the boil
2. distillationthe residue was distilled