Borane;tetrahydrofuran → Tert-butyl 4-(2-fluorophenyl)-4-(hydroxymethyl)piperidine-1-carboxylate

Participants

Reaction Steps

A flask was charged with 1-(tert-butoxycarbonyl)-4-(2-fluorophenyl)piperidine-4-carboxylic acid (1.51 g, 4.6 mmol) and tetrahydrofuran (10 mL). The reaction was placed under nitrogen. To the flask was added borane-tetrahydrofuran complex (1 M in tetrahydrofuran, 9.2 mL, 9.2 mmol). The reaction was allowed to stir at rt for 48 hr. The reaction was cooled to 0° C. and quenched with methanol (50 mL). The solution was then concentrated in vacuo. The residue was purified via column chromatography (25% ethyl acetate/75% hexanes→60% ethyl acetate/hexanes) to yield 1.0 g (70%) of the desired alcohol. 1H-NMR (CDCl3, 400 MHz) δ ppm 7.26 (m, 2H), 7.11 (m, 1H), 7.01 (m, 1H), 3.72 (m, 4H), 3.09 (m, 2H), 2.27 (m, 2H), 1.79 (m, 2H), 1.42 (s, 9H). Mass Spec.: 332.18 (MNa)+. LC: tr=3.301 min (Phenomenex-Luna 4.6×50 mm S10, 10% MeOH/90% H2O/0.1% TFA→90% MeOH/10% H2O/0.1% TFA Gradient Time=4 min, Flow rate=4 mL/min).

Provenance & Evidence