Boron tribromide → 5-ethyl-9-hydroxy-4-phenylpyrrolo[3,4-c]carbazole-1,3(2H,6H)-dione

Participants

Reaction Steps

Demethylation of (825) prepared as described in example 423 with BBr3 using the procedure described in example 80 gave (826) (97%), mp 190–196° C. 1H NMR δ [(CD3)2SO] 11.63 (s, 1H), 10.81 (s, 1H), 9.21 (s, 1H), 8.31 (d, J=2.4 Hz, 1H), 7.48–7.40 (m, 4H), 7.31–7.29 (m, 2H), 7.06 (dd, J=8.7, 2.4 Hz, 1H), 2.74 (q, J=7.4 Hz, 2H), 1.06 (t, J=7.4 Hz, 3H). Found: C, 72.43; H, 4.54; N, 7.54. C22H16N2O3.1/2H2O requires: C, 72.32; H, 4.69; N, 7.67.

Provenance & Evidence