Toluene → 2-(4-{2-[2-(4-Thiophen-2-yl-phenyl)-5-methyloxazol-4-yl]ethoxy}phenoxy)-2-methylpropionic acid ethyl ester

Participants

Reaction Steps

To a 25 mL round-bottomed flask equipped for magnetic stirring and fitted with a reflux condenser was added 2-(4-{2-[2-(4-bromophenyl)-5-methyloxazol-4-yl]ethoxy}phenoxy)-2-methyl propionic acid ethyl ester (0.410 mmoles, 200 mg) (see Ex. 2, part B), 2-thiophenyl boronic acid (0.451 mmoles), toluene (5 mL), ethanol (5 mL), and sodium carbonate (0.819 mmoles, 0.410 mL of a 2M solution). This mixture was vacuum degassed and nitrogen was added in at a positive pressure. Pd(PPh3)4 (catalytic, spatula tip) was added and the reaction was heated to reflux for 3 h. Distilled water was added to the mixture. Subsequently, this was extracted with ethyl acetate and washed with brine. The organic layer was collected, filtered over a thin pad of silica gel, and concentrated in-vacuo. The crude mixture was then purified by chromatography on silica gel affording 2-(4-{2-[2-(4-thiophen-2-yl-phenyl)-5-methyloxazol-4-yl]ethoxy}phenoxy)-2-methylpropionic acid ethyl ester.

Provenance & Evidence