Triphenylphosphine → 3-(2,2-dimethyl-indan-1-yl)-3H-imidazole-4-carboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

To a solution of 2,2-dimethyl-indan-1-ol (3.5 g, 21.6 mmol) in THF (160 mL) is added methyl 4-imidazolecarboxylate (CAS#17325-26-7, 4.1 g, 32.3 mmol), and triphenylphosphine (9.09 g, 34.5 mmol). The reaction is cooled to 0° C. and diisopropyl azodicarboxylate (6.67 mL, 34.5 mmol) is added. After one hour the reaction is diluted with saturated aqueous NaHCO3 and ethyl acetate. The layers are separated and the organic layer is dried with Na2SO4, filtered, and concentrated. The resulting residue is purified by silica gel flash chromatography (ethyl acetate-dichloromethane, 0:1 to 1:1) to provide 3-(2,2-dimethyl-indan-1-yl)-3H-imidazole-4-carboxylic acid methyl ester. HRMS: (ESI) m/z 271.1440 [(M+H)+: Calcd for C16H19N2O2: 271.1447]; 1H NMR (400 MHz, CDCl3) δ ppm 2.60-3.08 (m, 2 H), 3.92 (s, 3 H), 6.25 (s, 1 H), 7.03 (s, 1 H), 7.15-7.46 (m, 4 H), 7.80 (d, J=1.0 Hz, 1 H). The HCl salt of the title compound can be prepared by dissolution in diethyl ether followed by treatment with an excess of 1N HCl in diethyl ether. The resulting heterogeneous solution is concentrated to furnish the HCl salt of 3-(2,2-dimethyl-indan-1-yl)-3H-imidazole-4-carboxylic acid methyl ester.

Provenance & Evidence