反应详情

Ethyl [(2-oxo-2-phenylethyl)thio]acetate (10.8 g, 45.3 mmol) was dissolved in toluene (250 ml). 2,2-Dimethyl-1,3-propanediol (37.6 g, 0.36 mol) and p-toluene sulfonic acid (cat., 500 mg) were added. The mixture was stirred at reflux in a Dean-Stark apparatus for two hours and at room temperature overnight. The mixture was concentrated under reduced pressure. The crude oil was purified by flash-chromatography (hexane:EtOAc-7:1) to give 11.2 g (70%) of the title compound as a colourless oil. 1H-NMR (CDCl3, 200 MHz): δ 0.6 (s, 3H), 1.2-1.3 (t, 3H), 1.4 (s, 3H), 3.0 (s, 2H), 3.2 (s, 2H), 3.5 (s, 4H), 4.1-4.2 (q, 2H), 7.3-7.6 (m, 5H).

1. concentrationThe mixture was concentrated under reduced pressure
2. customThe crude oil was purified by flash-chromatography (hexane:EtOAc-7:1)