反应详情

(R)-3-hydroxybutyric acid (Fluka-5.0 g: 0.048 mole), p-toluene sulphonic acid (0.025 g) and benzene (100 ml) were stirred under reflux withn a Dean-Stark trap arrangement for 24 hours. The reaction mixture was cooled and the benzene evaporated in vacuo (0.5 mm Hg). 4.4 g of colourless oil was obtained of which a 20 mg sample was converted to the methyl ester for analysis of number of monomer repeats using NMR. These studies show that the product is a mixture of oligomers of D-β-hydroxybutyrate of average number of repeats 3.75, being mainly a mixture of trimers, tetramers and pentamers with the single most abundant material being the tetramer. The product mixture was soluble in 1 equivalent of sodium hydroxide.

1. additiona mixture of trimers, tetramers and pentamers with the single most abundant material