p-Toluenesulfonic acid → 4-[1,3]Dioxan-2-yl-butyric acid methyl ester

Participants

Reaction Steps

Methyl 5,5-dimethoxyvalerate (20.0 g, 0.114 mol), propane-1,3-diol (13 g, 0.17 mol) and para-toluene sulphonic acid (2.17 g, 0.0114 mol) were heated under Dean-Stark conditions in toluene (100 ml) for 4 h. The mixture was cooled to room temperature and diluted with diethyl ether (100 ml) and then neutralized with solid sodium bicarbonate. The solid was filtered and the filtrate evaporated to give a pale yellow oil (22.3 g). A 10 g portion of this was then purified by silica gel chromatography (eluent 30% EtOAc:hexane) which gave the title compound as a colourless oil (6.82 g).

Provenance & Evidence