Tetrahydrofuran → Benzyl 3-hydroxycyclopentanecarboxylate

Participants

Reaction Conditions

Reaction Steps

A solution of (−)-α-pinene (5.80 g, 42.6 mmol) in THF (10 mL) was cooled to 0° C. and a solution of borane-Me2S (10N, 1.5 mL, 15 mmol) was added. The mixture was stirred for 4 h at 0° C. and benzyl cyclopent-3-enecarboxylate (3.5 g, 17 mmol) was added. The reaction mixture was allowed to warm to ambient temperature and stirred overnight. The mixture was cooled to 0° C. again and quenched with water (2 mL) and aqueous NaOH (3N, 15 mL). Then 30% hydrogen peroxide (20 mL) was added dropwise. The mixture was stirred for 1 h at 0° C. and diluted with water (20 mL) and EtOAc (50 mL). The two layers were separated and the aqueous phase was extracted with EtOAc (50 mL×3). The combined organic phases were washed with brine (200 mL×3), dried over anhydrous sodium sulfate, and concentrated. The residue was purified by flash column chromatography on silica gel (EtOAc/hexane=1:4) to afford benzyl 3-hydroxycyclopentanecarboxylate (1.4 g, 37% yield).

Provenance & Evidence