Synthesis and Isolation of iodocarbazoles. Direct iodination reaction of N-substituted carbazoles

M. E. MONGE, S. M. BONESI, R. ERRA-BALSELLS

JOURNAL OF HETEROCYCLIC CHEMISTRY

HeteroCorp

Lugar: USA; Año: 2002 vol. 39 p. 933 - 941

0022-152X

Iododerivatives of N-Methylcarbazole (1), N-phenylcarbazole (2), N-benzylcarbazole (3), 2-methoxy-N-methylcarbazole (4) and 3-acetamido-N-ethylcarbazole (5) are synthetized. N-iodosuccinimide (NIS) in TH/H2SO4 /catalyst), a mixture of KIO3 - KI - H2SO4 (catalyst) in ethanol and a mixture of KIO3 - IK in acetic acid as iodinating agents have been used and their uses have been compared. The preparation and characterization of compounds 1a, 1b, 1c, 1d, 2a, 2b, 3a, 3b, 4a, 4b, 4c and 5a are reported (mp,tR, Rf, 1H-NMR, 13C-nmr, IR, ms). All of them are described for the first time except 3,6-diiodo-N-phenylcarbazole (2b). Semiempirical PM3 calculations have been performed to predict reactivity of N-substituted carbazoles and their iododerivatives. Theoretical and experimental results are discussed briefly.