Triphenylphosphine → 2-Chlorobenzenesulfonic acid 3-[[N-(tert-butoxycarbonyl)piperidin-4-yl]methoxy]-5-methylphenyl ester

Participants

Reaction Conditions

Reaction Steps

A solution of 2-chlorobenzenesulfonic acid 3-hydroxy-5-methylphenyl ester (600 mg, 2.0 mmol), as prepared in the preceding step, N-(tert-butoxycarbonyl)-4-piperidinemethanol, as prepared in step f of Example 1, (430 mg, 2.0 mmol) and triphenylphosphine (525 mg, 2.0 mmol) in tetrahydrofuran (15 mL) at 0° C. was treated with diethyl azodicarboxylate (349 mg, 2.0 mmol). The reaction mixture was stirred at 0° C. for 2 h and at room temperature for 3 h. The reaction mixture was partitioned between ethyl acetate (200 mL) and water (50 mL). The organic extract was washed sequentially with saturated NaHCO3 (2×50 mL) and brine (2×50 mL), dried over Na2SO4, and concentrated in vacuo. The residue was purified by flash column chromatography (2:1 ethyl acetate:hexane) to give the title compound as a colorless syrup (895 mg, 90%). 1H-NMR (300 MHz, CDCl3) δ 1.24 (m, 2H), 1.47 (s, 9H), 1.80 (d, 2H), 1.89 (m, 1H), 2.24 (s, 3H), 2.72 (t, 2H), 3.68 (d, 2H), 4.13 (m, 2H), 6.47 (t, 1H), 6.52 (d, 1H), 6.58 (d, 1H), 7.38 (t, 1H), 7.61 (m, 2H), 7.97 (dd, 1H).

Provenance & Evidence