4-Hydrazinylbenzenesulfonamide hydrochloride → 4,5-dihydro-4-[3-(trifluoromethyl)-1H-benz[g]indazol-1-yl]benzenesulfonamide

Participants

Reaction Steps

A 100 mL one necked round bottomed flask equipped with reflux condenser, nitrogen inlet and provisions for magnetic stirring was charged with 2trifluoroacetyl-1-tetralone (1.21 g, 5.0 mmol), 4-sulfonamido phenylhydrazine hydrochloride (1.12 g, 5.0 mmol) and 25 mL of absolute ethanol. The solution was then warmed to reflux for 15 h and then concentrated in vacuo. The residue was dissolved in ethyl acetate and then washed with water, brine, dried over anhyd. MgSO4, filtered and concentrated in vacuo. The residue was recrystallized from a mixture of ethyl acetate and isooctane to give g, 71% of pure product with mp 257°-258° C. 1H NMR (CDCl3 /CD3OD, 4:1) δ 2.7 (m, 2H), 2.9 (m, 2H), 6.6 (m, 1H), 6.9 (m, 1H), 7.1 (m, 1H), 7.16 (m, 1H), 7.53 (m, 2H), 7.92 (m, 2H); 19F NMR CDCl3 δ -62.5. FAB-MS M+H=394.

Provenance & Evidence