Phosphorus trichloride → 2-(4-Chlorophenyl)-5-cyclopropyl-6-nitro-2H-indazole-3-carbonitrile

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of the crude intermediate 2-(4-chlorophenyl)-5-cyclopropyl-6-nitro-2H-indazole-3-carbonitrile 1-oxide (23 g, 0.06 mmol) in chloroform (230 mL) was added phosphorus trichloride (23 mL) and the reaction mixture was then heated at 60° C. After 2 h, the reaction was cooled to RT and ice-water added (ca. 200 mL). The organics were extracted into DCM (3×200 mL), dried (Na2SO4) and concentrated in vacuo to give (v) (20.3 g, 92%), which was used unpurified in subsequent steps. ESI-MS m/z calculated for [M+H]+: 339.1. found: 339.0. 1H NMR (400 MHz, CDCl3) δ 8.25 (s, 1H), 7.92-7.81 (m, 2H), 7.69-7.57 (m, 3H), 2.42-2.29 (m, 1H), 1.14-1.03 (m, 2H), 0.82-0.72 (m, 2H).

Provenance & Evidence