Potassium Carbonate → 2-Methyl-3-(4-{2-[5-methyl-2-(4-thiophen-2-yl-phenyl)-oxazol-4-yl]-ethoxy}-phenyl)-2-m-tolyloxy-propionic acid

Participants

Reaction Steps

A mixture of 2-(m-tolyloxy)-3-(4-hydroxyphenyl)-2-methyl-propionic acid ethyl ester (0.095 g, 0.030 mmol) (see Ex. 48, Part C), toluene-4-sulfonic acid 2-(5-methyl-2-(4-thiophen-2-yl-phenyl)-oxazol-4-yl)ethyl ester (0.030 mmol) and 325 mesh K2CO3 (0.084 g, 0.60 mmol) in ethanol (2 mL) was heated to reflux for 24 h under N2. Aqueous 5N NaOH (0.5 mL) and additional ethanol (1 mL) was added to the reaction mixture and it was heated at reflux for an additional 2 h. The reaction was cooled and the solvent removed in vacuo. The residue was acidified with aqueous 1 N HCl (5 mL), extracted with water and CH2Cl2 and the organic layer dried by passing it through a Varian Chem Elut 1003 cartridge. The solvent was removed in vacuo to give 2-methyl-3-(4-{2-[5-methyl-2-(4-thiophen-2-yl-phenyl)-oxazol-4-yl]-ethoxy}-phenyl)-2-m-tolyloxy-propionic acid. 1H NMR (400 MHz, CDCl3) δ 7.97 (d, 2H, J=8.60 Hz), 7.68 (d, 2H, J=8.60 Hz), 7.40 (d, 1H, J=3.52 Hz), 7.34 (d, 1H, J=4.69 Hz), 7.18 (d, 2H, J=8.21 Hz), 7.15–7.09 (m, 2H), 6.87–6.82 (m, 3H), 6.72–6.69 (m, 2H), 4.22 (t, 2H, J=6.26 Hz), 3.23 (d, 1H, J=14.08 Hz), 3.13 (d, 1H, J=14.08 Hz), 3.03 (t, 2H, J=6.26 Hz) 2.41 (s, 3H), 2.29 (s, 3H), 1.42 (s, 3H); HRMS (ES+) m/z exact mass calcd for C33H32NO5S 554.2001, found 554.2022.

Provenance & Evidence