Methanol → 9-Ethyl-3-isocyanatocarbazole

Participants

Reaction Steps

38.6 g of 3-amino-9-ethylcarbazole and 27.9 ml of triethylamine were added to 300 ml of methanol, and, while cooling with ice, 15.2 g of carbon disulfide was added dropwise thereto. After conducting reaction at room temperature for 3 hours, 41.3 g of dicyclohexylcarbodiimide was added thereto, followed by reacting at room temperature for 4 hours. Crystals thus precipitated were collected by filtration, heat-refluxed for 10 minutes in 500 ml of ethyl acetate, and cooled to precipitate and then filter off solids. The filtrate was concentrated by removing solvents in vacuo to obtain the desired product (29 g).

Provenance & Evidence