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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).

1. customTo a 3 neck 1-liter round bottomed flask equipped with a stirring bar, argon inlet
2. additionThis solution was added to the cold acid mixture, dropwise over 1 hour
3. additionWhen the addition
4. customthe cooling bath was removed
5. temperatureto warm to room temperature
6. customThe reaction was then quenched by careful addition of water (200 ml)
7. additionThe resulting solution was diluted with 600 ml of ether which
8. customresulted in a phase separation
9. customThe organic layer was separated
10. washwashed
11. customDrying
12. filtration(MgSO4), filtration, and removal of the solvent in vacuo
13. waitleft 25 g of a solid which
14. customwas recrystallized