p-Toluenesulfonic acid → HCID 19021020, compound

Participants

Reaction Steps

A solution of compound 5 (2.5 g, 0.013 mole), triethyl orthoformate (3.87 g, 0.026 mole) in 20 ml ethanol and p-toluenesulfonic acid (35 mg) was refluxed for 18 hours. Upon cooling, the mixture was treated with 0.2 ml of triethylamine and extracted with diethyl ether. The extract was then washed successively with NaHCO3 solution, water and brine. After drying (MgSO4), the solvent was removed in vacuo. The residual brown oil was purified by column chromatography on silica gel, using diethyl ether/hexane (4/1) as eluant. The product was obtained as a light brown oil; 2.2 g; IR (neat) 1625 cm-1 ; NMR (CDCl3) δ6.3 (s, 1H); 4.6 (t, 1H); 3.85 (t, 2H); 3.4-3.8 (m, 4H); 2.0 (q, 2H); 1.2 (t, 6H).

Provenance & Evidence