Hydrochloric Acid → 5-{[2-Tert-butyl-4-(2-hydroxyethoxy)-5-methylphenyl]sulfanyl}-6-hydroxy-2-[4-(2-hydroxyethoxy)phenyl]-2-(2-phenylethyl)-2,3-dihydro-4h-pyran-4-one

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Reaction Steps

To a round bottom flask equipped with a magnetic stirrer were added 6-{4-[2-(tert-butyl-dimethyl-silanyloxy)-ethoxy]-phenyl} -4-hydroxy-6-phenethyl-5,6-dihydro-pyran-2-one (prepared in Example SS; 0.260 g, 0.555 mmol), toluene-4-thiosulfonic acid S-{2-tert-butyl-4-[2-(tert-butyl-dimethyl-silanyloxy)-ethoxy]-5-methyl-phenyl) ester (prepared in Example PPP; 0.282 g, 0.555 mmol), K2CO3 (0.346 g, 2.50 mmol), and DMF (5 mL), as described in General Method 9. The mixture was stirred at room temperature for 2 days at which time MeOH (150 mL) was added and the solution taken to pH 3.0 with conc. HCl. The reaction was quenched with H2O (500 mL) and extracted with EtOAc. The organics were dried over MgSO4 and concentrated; the residue was taken up in a small amount of EtOAc and triturated with hexane. The solid was filtered and dried under high vacuum to yield the title compound, m.p. >190° C. (dec.). 1H NMR (DMSO-d6) δ 1.45 (s, 9 H), 1.68 (s, 3 H), 2.22 (br m, 4 H), 2.51 (br m, partially obscured by DMSO, 2 H), 3.34 (d of ABX q, partially obscured by H2 0, 1 H), 3.40 (d of ABX q, partially obscured by H2O, 1 H), 3.67 (br m, 2 H), 3.72 (br m, 2 H)3.91 (t, 2 H), 3.98 (t, 2 H), 6.76 (s, 1 H), 6.96 (s, 1 H), 6.99 (d, 2 H), 7.08-7.22 (m, 1 H), 7.10 (d, 2 H), 7.24 (d, 2 H), 7.30 (d, 2 H).

Provenance & Evidence