Phosphoric Acid → 2-(6-((5-(4-Chlorophenyl)isoxazol-3-yl)methoxy)-5-methylbenzo[b]thiophen-3-yl)acetic acid

Participants

Reaction Steps

Compound 79A (0.03 g, 0.07 mmol) from the preceding step was dissolved in 2-3 mL of tetrahydrofuran, an equal volume of 2N KOH was added, and the mixture stirred at room temp. After 18 hours 75 mL of icewater was added and the mixture was acidified with H3PO4. After 30 min the precipitate was filtered off, rinsed 3× with water, and dried. The product was triturated in 4N HCl, allowed to stand for an hour, then filtered off, rinsed with water then ethanol, and dried to afford 0.01 g (99%) of the title compound as a white powder; mp 198-200° C. (dec). MS m/z 413 (M). Synthesis of {6-[5-(4-Trifluoromethyl-phenyl)-isoxazol-3-ylmethoxy]-benzofuran-3-yl}-acetic acid (Compound 80) Step 1. Preparation of {6-[5-(4-Trifluoromethyl-phenyl)-isoxazol-3-ylmethoxy]-benzofuran-3-yl}-acetic acid methyl ester (Compound 80A)

Provenance & Evidence