Iodoethane → 5-Bromo-3-cyclobutyl-1-ethyl-1H-indazole

Participants

Reaction Conditions

Reaction Steps

The 5-bromo-3-cyclobutyl-1H-indazole intermediate (1.501 g, 5.97 mmol) was dissolved in anhydrous DMF (25 mL), cooled to 0° C. and treated with a 60% dispersion of sodium hydride in mineral oil (330 mg, 8.26 mmol). The cold bath was removed and the reaction mixture was stirred at room temperature for 2 h after which time iodoethane (1.034 g, 6.62 mmol) was added and the reaction mixture was stirred 8 h. The reaction mixture was then cooled and quenched by addition of a saturated aqueous solution of NH4Cl (10 mL) then extracted with EtOAc (20 mL). The organic extract was dried over MgSO4, filtered, and evaporated to an oil, which was purified by silica gel flash chromatography with a 0-10% EtOAc/hexanes gradient to afford titled compound as a light yellow oil (1.14 g, 68%). 1H NMR (DMSO-d6) 7.90 (s, 1H), 7.58 (d, J=8.5, 1H), 7.44 (d, J=8.5, 1H), 4.35 (q, J=7.2, 2H), 3.85 (pent, J=7.6, 1H), 2.35-2.31 (m, 4H), 2.31-2.02 (m, 1H), 1.99 (m, 1H), 1.35 (t, J=7.6, 3H). LC/MS (Method B) 4.27 min, [M+1]+ 279/281.

Provenance & Evidence