Sulfuric Acid → 3-Azido-1,5,5-trimethyl-1-cyclohexene

Participants

Reaction Steps

To a cooled (0° C.) suspension of sodium azide (0.81 g, 12.5 mmol) in CH2Cl2 (5 ml) was added dropwise 53% aqueous H2SO4 (8 ml). The mixture was stirred for 10 min, then a solution of 3,5,5-trimethyl-2-cyclohexanol (33) (0.70 g, 5 mmol) in CH2Cl2 (8 ml) was added. The mixture was stirred for 20 h, poured into ice water, neutralized with aqueous NH4OH and extracted with CH2Cl2. The extract was washed with brine and dried over MgSO4. Filtration and evaporation of the solvent keeping the temperature below 25° C. gave an oil which was separated by column chromatography on silica gel (light petroleum ether). A fraction with Rf 0.8 (hexane) was collected. Evaporation of the solvent gave 34 as a colorless oil (0.365 g, 44%). 1H NMR (CDCl3, TMS): 0.89 and 1.01 (total 6H, both s, 5,5-CH3); 1.34 (1H, m, c-4-CH); 1.55-1.95 (3H, m, 4-CH, 6-CH2); 1.71 (3H, s, 1-CH3); 3.90 (1H, m, 3-CH) and 5.39 ppm (1H, s, C═CH).

Provenance & Evidence