Hydroxylamine → Cyclohexanemethanol, alpha-ethyl-, 1-acetate

Participants

Reaction Steps

To a vial containing aminoalcohol 1 (0.05 g, 0.17 mmol) prepared as in Example 1 was added a solution containing freshly distilled cyclohexane-carboxaldehyde (0.34 g, 3.0 mmol), toluene (3.0 mL), and 1 M diethylzinc in hexane (6.0 mL). After 3 days at room temperature, acetic anhydride (1.2 mL, 13 mmol) was added. After 2 additional days, the mixture was diluted in ether (50 mL) and the reaction was quenched by dropwise addition of half-saturated aqueous ammonium chloride (50 mL). The ether layer was separated and the aqueous layer was further extracted with ether (2×50 mL). The combined ether layers were dried over magnesium sulfate whereupon the solvent was removed at reduced pressure. The residue was purified by flash chromatography on 220-400 mesh silica with 90% hexane and 10% ethyl acetate as eluant. The product (+)-1-cyclohexylpropyl acetate (0.45 g, 81%) was isolated as a colorless liquid by distillation at reduced pressure. Anal. for C11H20O2. Calcd: C, 71.70; H, 10.94; found: C, 71.41; H, 10.69. 1H NMR (CDCl3/TMS): δ 0.85 (t, 3 H, J=7), 0.98 (m, 2 H), 1.08-1.26 (m, 3 H), 1.42-1.75 (m, 8 H), 2.04 (s, 3 H), 4.66 (m, 1 H). 13C NMR (CDCl3/TMS): δ 9.80, 21.14, 24.11, 26.21, 26.58, 28.22, 40.90, 79.25, 171.09. [α]D25=+27.6, c=2.06 g/100 mL chloroform. Chiral capillary gas chromatographic analysis at 120° C. on Cyclodex B stationary phase (J & W Scientific) indicated that the enantiomeric excess of the product was 97%.

Provenance & Evidence