On the synthesis and isolation of chlorocarbazoles obtained by chlorination of N ‐substituted carbazoles

Chloro derivatives of N ‐methylcarbazole ( 1 ), N ‐phenylcarbazole ( 2 ), N ‐acetylcarbazole ( 3 ), N ‐benzoylcarbazole ( 4 ) and 2‐methoxy‐ N ‐methylcarbazole are synthesized. They are compounds 1a, 1b, 1c, 1d, 1e, 2a, 2b, 3a, 3b, 3c, 3d, 4a, 4b, 5a, 5b, 5c, 5d and 5e . Some of them are described for the first time. By using semiempirical PM3 method theoretical substituent effects on the chlorinating reaction are calculated. A chlorination mechanism of carbazoles and N ‐substituted carbazoles are compared.