Carbon tetrabromide → Ethyl 1-({4-[3-(4-isobutylphenyl)isoxazol-5-yl]-2-thienyl}methyl)azetidine-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

A solution of {4-[3-(4-isobutylphenyl)isoxazol-5-yl]-2-thienyl}methanol (0.43 g, 1.4 mmol) that was obtained in Example 9 (9g), carbon tetrabromide (0.68 g, 2.1 mmol) and triphenylphosphine (0.54 g, 2.1 mmol) in dichloromethane (15 ml) was stirred at 0° C. for 5 minutes. Subsequently, to the reaction mixture were added successively ethyl 3-azetidinecarboxylate hydrochloride (0.34 mg, 2.1 mmol) and N,N-diisopropylethylamine (0.60 ml, 3.4 mmol) with stirring, and the resulting mixture was stirred at room temperature for 18 hours. After stirring, a saturated aqueous solution of sodium hydrogencarbonate (5 ml) was added to the reaction mixture to quench the reaction, and the resulting mixture was poured into water (50 ml) and extracted with dichloromethane. The extract was washed with a saturated aqueous solution of sodium chloride and dried over magnesium sulfate. After filtration, the filtrate was evaporated in vacuo, and the crude product of the title compound thus obtained was purified by chromatography on a silica gel column using a mixed solvent of ethyl acetate and hexane (1:4 to 3:2) as the eluent to afford the title compound (0.48 g) in a yield of 82% as a white crystalline solid.

Provenance & Evidence