Benzene → 1-tert-butoxycarbonyloxy-6-chloro-1H-benzotriazole

Beteiligte Stoffe

Reaktionsschritte

A solution of phosgene (5 g.) in benzene (23.5 ml.) was dropwise added under ice-cooling to a suspension of 1-hydroxy-6-chloro-1H-benzotriazole (8.5 g.) and pyridine (3.9 g.) in benzene (50 ml.), and the mixture was stirred for 30 minutes at the same temperature and allowed to stand overnight. To the resultant solution containing 1-chlorocarbonyloxy-6-chloro-1H-benzotriazole was dropwise added, over 20 minutes under ice-cooling, a solution of tert-butyl alcohol (3.7 g.) and pyridine (4.0 g.) in benzene (50 ml.). The resultant mixture was stirred for 2 hours at the same temperature and allowed to stand overnight. The reaction mixture was filtered, and the filtrate was concentrated. Ether and petroleum ether were added to the residue to pulverize the residue and obtained crystals were collected by filtration to give 1-tert-butoxycarbonyloxy-6-chloro-1H-benzotriazole (5.3 g.). The mother liquor was concentrated to give the same object compound (0.6 g.). Both crystals were put together and dissolved in benzene, after which the solution was washed with a sodium bicarbonate aqueous solution and water and then dried. The solvent was removed by distillation to give the object compound (3.2 g.), powder, mp 98° to 100° C (dec.).

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