Hydrochloric Acid → HCID 22291456, compound

Participants

Reaction Steps

A suspension of ethyl 1-(4-bromophenyl)-8-nitro-4,5-dihydro-1H-benzo[g]indazole-3-carboxylate (4.4 g) in THF (80 mL) was treated with 1 N aq. NaOH (80 mL) and stirred vigorously overnight. The reaction mixture was diluted with ethyl acetate and acidified to pH=2 with 1 N aq. HCl. The organic layer was separated and the aqueous fraction extracted with EtOAc (3×). Combined extracts were washed with brine, dried over Na2SO4, filtered and concentrated in vacuo to afford 4.0 g (97%) of 1-(4-bromophenyl)-8-nitro-4,5-dihydro-1H-benzo[g]indazole-3-carboxylic acid as a solid: MS(ESI+) 414 [M+H]+. 1H NMR (400 MHz, d6 DMSO) δ 8.07 (dd, 1H), 7.83 (d, 2H), 7.66 (d, 1H), 7.56 (d, 2H), 7.42 (d, 1H), 3.10 (m, 2H), 2.99 (m, 2H).

Provenance & Evidence