Imidazole → Dechloroclotrimazole

Participants

Reaction Steps

To a solution of trityl chloride (5.58 g, 20.0 mmol.) in dry methylene chloride (100 ml) cooled down to 0° C. and stirred under Ar, was added dropwise over 1.5 hours a solution of imidazole (1.36 g, 20.0 mmol.) and triethylamine (2.7 mml, 20 mmol.) in 50 ml dry methylene chloride. At the end of the addition, the reaction mixture was allowed to warm up to room temperature and stirred under Ar at that temperature overnight. The reaction mixture was then washed with 20 ml of a 10% solution of ammonium chloride, then with 20 ml of distilled water. The organic phase was dried over magnesium sulfate and evaporated in vacuo to yield quantitatively a white solid. Recrystallization from methylene chloride/hexanes yielded 5.60 g of (5) (yield=90% after recrystallization). m.p. 214° C.; 1H NMR (200 MHz, CDCl3) δ 7.43 (m, 1H, NCHN), 7.3-7.4 (m, 9H, 3×C6H5), 7.1-7.2 (m, 6H, 3×C6H5), 7.0 (m, 1H, Ph3CNCH═CH), 6.81 (m, 1H, Ph3CNCH═CH); 13C NMR (50 MHz, CDCl3) δ 142.3, 139.0, 129.6, 128.2, 128.3, 121.6.

Provenance & Evidence