Diisobutylaluminumhydride → 3-(4-Bromo-pyrazol-1-yl)-3-methyl-butan-1-ol

Participants

Reaction Conditions

Reaction Steps

Diisobutylaluminium hydride (1 M in toluene, 10.43 mL) was added dropwise to a solution of ethyl 3-(4-bromo-1H-pyrazol-1-yl)-3-methylbutanoate (Compound 50E, 1.3 g, 4.74 mmol), in THF (30 mL) at −78° C. and allowed to stir for 3 hours eventually warming to −10° C. The reaction mixture was quenched with an aqueous solution of K/Na tartrate tetrahydrate (10 mL) and allowed to stir for 2 hours. The mixture was extracted with ethyl acetate (3×15 mL) and the combined organic extracts were washed with water, followed by brine, dried over sodium sulfate, filtered and concentrated to afford 1.0 g of the desired product (91%). 1H NMR (300 MHz, CDCl3) δ 7.51 (s, 1H), 7.46 (s, 1H), 3.54-3.58 (q, J=4.5 Hz, 2H), 2.28 (t, J=4.2 Hz, 1H), 2.09 (t, J=4.5 Hz, 2H), 1.58 (s, 6H).

Provenance & Evidence