Camphoric Acid → rel-(1R,3S)-1,2,2-Trimethyl-1,3-cyclopentanedimethanol

Participants

Reaction Steps

A solution of (1R,3S)-1,2,2-trimethylcyclopentane-1,3-dicarboxylic acid (26.25 g, 131 mmol) in THF (400 mL) was cooled in an ice bath (10° C.) and to this was added 1M LiAlH4/THF (328 mL, 328 mmol), dropwise over 1 h. The ice bath was removed and the white slurry was stirred for 5 h at room temperature and 17 h at reflux. After cooling to room temperature, the mixture was diluted with Et2O (500 mL), cooled in an ice bath and carefully quenched with water (12.2 mL), 15% NaOH (12.2 mL) and water (36.7 mL). After stirring for 30 min at room temperature, the white slurry was filtered through a pad of CELITE®, then dried (Na2SO4), filtered and concentrated to give ((1R,3S)-1,2,2-trimethylcyclopentane-1,3-diyl)dimethanol (21.665 g, 126 mmol, 96% yield) as a white solid. 1H NMR (500 MHz, CDCl3) δ: 3.73 (1 H, dd, J=10.2, 5.3 Hz), 3.58 (1 H, d, J=10.7 Hz), 3.51 (1 H, dd, J=10.1, 8.5 Hz), 3.46 (1 H, d, J=10.7 Hz), 2.04-2.12 (1 H, m), 1.89-1.99 (1 H, m), 1.55-1.64 (1 H, m), 1.31-1.41 (2 H, m), 1.22 (2 H, brs), 1.02 (3 H, s), 1.01 (3 H, s), 0.78 (3 H, s).

Provenance & Evidence