Water → HCID 22733808, compound

Participants

Reaction Steps

2.46 g (61.4 mmol, 1.05 equiv) sodium hydride, 60% oil dispersion, was added in 0.5 g portions to a 10° C. solution of 13.17 g (58.5 mmol, 1.0 equiv) 6-bromo-3-ethyl-1H-indazole in 500 mL anhydrous DMF. The mixture was stirred at room temperature for 20 minutes, then a solution of 8.8 mL (81.9 mmol, 1.4 equiv) cyclopentyl bromide in 10 mL anhydrous DMF was added dropwise. After 18 hours, the reaction mixture was poured into 2 L H2O and extracted 2×1 L ethyl acetate. The organic extracts were combined, washed 2×750 mL H2O, 1×500 mL brine, and dried over Na2SO4. Filtration, concentration of filtrate and drying gave 20.7 g of crude product, which was purified on a silica gel column (1.1 kg silica gel, 3% ethyl acetate/hexanes) to give 10.6 g (62%) of an amber liquid: IR (CHCl3)2972, 2875, 1606, 1501, 1048 cm−1 ; 1H NMR (300 MHz, CDCl3) d 7.56 (d, 1H, J=1.3 Hz), 7.52 (d, 1H, J=8.7 Hz), 7.17 (dd, 1H, J=1.5, 8.5 Hz), 4.83 (quintet, 1H, J=7.6 Hz), 2.96 (q, 2H, J=7.6 Hz), 2.15 (m, 4H), 2.0 (m, 2H), 1.65 (m, 2H), 1.36 (t, 3H, J=7.7 Hz); MS (thermospray, NH4OAc) m/z 295/293 (M+H+, base); Anal. calcd for C14H17N2Br: C, 57:35; H, 5.84; N, 9.55. Found: C, 57.48; H, 5.83; N, 9.90.

Provenance & Evidence