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

Participants

Reaction Steps

9-Hydroxy-4-(3-methoxyphenyl)pyrrolo[3,4-c]carbazole-1,3(2H,6H)-dione (prepared as decribed in example 35) was reacted with BBr3 using the procedure described in the proceedure described in example 80 of Scheme 2 to give 9-hydroxy-4-(3-hydroxyphenyl)pyrrolo[3,4-c]carbazole-1,3(2H,6H)-dione (25) (I, Ar=3-hydroxyphenyl) in a yield of 88%; mp 282–285° C. (dec). 1H NMR δ [(CD3)2SO] 11.73 (br s, 1H), 11.00 (br s, 1H), 9.48 (br s, 1H), 9.24 (s, 1H), 8.34 (d, J=2.4 Hz, 1H), 7.54 (s, 1H), 7.43 (d, J=8.7 Hz, 1H), 7.24 (dd, J=7.7, 7.7 Hz, 1H), 7.05 (dd, J=8.7, 2.4 Hz, 1H), 7.01–6.96 (m, 2H), 6.82 (dd, J=8.2, 2.1 Hz, 1H). FABMS found [M+H]+: 345.0865. C20H13N2O4 requires 345.0875.

Provenance & Evidence