Tetrahydrofuran → HCID 67975086, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-methyl-1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazole (0.258 g, 1.55 mmol) in tetrahydrofuran (6 mL, 70 mmol) at −78° C. was added 2.5 M of n-butyllithium in hexane (0.80 mL). The reaction was stirred at −78° C. for 50 minutes, and then tributyltin chloride (0.60 mL, 2.2 mmol) was added. The reaction was kept at −78° C. for 2 hours and then quenched with saturated aqueous NH4Cl and warmed to room temperature. The reaction mixture was diluted with more water and extracted with ethyl acetate. The organic portion was dried with MgSO4, filtered, and evaporated in vacuo. The crude product was purified via flash chromatography on silica gel (40 g silica, solvent gradient: 0-50% ethyl acetate in heptanes) to yield 520.6 mg (74%) of 4-methyl-1-(tetrahydro-2H-pyran-2-yl)-5-(tributylstannyl)-1H-pyrazole. LCMS (ESI): M+H=457.2; 1H NMR (400 MHz, DMSO-d6) δ 7.31 (s, 1H), 5.11 (d, J=8.3 Hz, 1H), 3.81 (d, J=11.4 Hz, 1H), 3.59-3.48 (m, 1H), 2.23 (dd, J=20.7, 9.4 Hz, 1H), 2.04 (s, 3H), 1.97 (d, J=12.8 Hz, 1H), 1.90 (d, J=13.3 Hz, 1H), 1.48 (m, 9H), 1.30 (dd, J=14.5, 7.3 Hz, 6H), 1.20-0.97 (m, 6H), 0.86 (t, J=7.3 Hz, 9H).

Provenance & Evidence