Borane → 2-(Bromomethyl)benzyl alcohol

Participants

Reaction Conditions

Reaction Steps

To a 3 neck 1-liter round bottomed flask equipped with a stirring bar, argon inlet, and pressure equalizing dropping funnel was added o-bromomethylbenzoic acid (35 g, 163 mmol) and 70 ml of dry tetrahydrofuran (THF). The slurry-solution was cooled in a 0° C. ice-salt bath and the dropping funnel was charged with a solution of borane in THF (212 ml of a 1.0 M solution, 212 mmol). This solution was added to the cold acid mixture, dropwise over 1 hour. When the addition was complete, the cooling bath was removed and the mixture was allowed to warm to room temperature and stir for 1 hour. The reaction was then quenched by careful addition of water (200 ml). The resulting solution was diluted with 600 ml of ether which resulted in a phase separation. The organic layer was separated and washed: H2O (2×500 ml) and brine (1×500 ml). Drying (MgSO4), filtration, and removal of the solvent in vacuo left 25 g of a solid which was recrystallized from boiling ethyl acetate-hexane to give the compound (1a): mp 61°-63° C.; 'H NMR (CDCl3) δ2.05 (s, 1H), 4.60 (s, 2H), 4.80 (s, 2H), 7.20-7.55 (m, 4H).

Provenance & Evidence