Oxazole → 2,5-Diphenyloxazole

Participants

Reaction Steps

FIG. 11 shows the molecular structures of the resultant molecule 2-phenyloxazole when the starting heterocycle is 1,3-oxazole, and its 1H NMR spectrum. 2,5-Diphenyloxazole is also produced in the synthesis. The synthesis of 2-phenyloxazole and 2,5-diphenyloxazole is conducted using copper(I) iodide (19.1 mg, 0.1 mmol), oxazole (69 mg, 1.0 mmol), iodobenzene (612 mg, 3.0 mmol), t-BuOLi (160 mg, 2.0 mmol), and DMF (1.0 mL). After column chromatography (hexanes, then 10% ethyl acetate in hexanes) and preparative HPLC (5% ethyl acetate in hexanes) 15 mg (7%) of a light tan solid (2,5-diphenyloxazole, Rf=0.30 (1/9 ethyl acetate/hexanes)) and 85 mg (59%) of a colorless oil (2-phenyloxazole, Rf=0.27 (1/9 ethyl acetate/hexanes)) are obtained. 1H NMR spectrum for 2-Phenyloxazole (300 MHz, CDCl3): δ7.23 (s, 1H), 7.42-7.49 (m, 3H), 7.71 (s, 1H), 8.01-8.10 (m, 2H). 1H NMR spectrum for 2,5-Diphenyloxazole (300 MHz, CDCl3): δ 7.31-7.38 (m, 1H), 7.40-7.52 (m, 6H), 7.70-7.75 (m, 2H), 8.08-8.15 (m, 2H). Table III, entry 1.

Provenance & Evidence