A convenient preparative method of 3-hydroxy acids, and the reaction of 3-hydroxy acids with acidic materials

Abstract

3-Hydroxy acids were synthesised in good yield from ketones and carboxylic acids using lithium naphthalenide in the presence of diethylamine. From cyclohexanone and propionic acid, 2-(1′-hydroxycyclohexan-1′-yl) propionic acid (I) was obtained in 98.3% yield. 3-Hydroxy acids were treated with various acidic materials to give 3,4-unsaturated carboxylic acids and γ-butyrolactones. From the reaction of (I) with p-toluenesulphonic acid or potassium bisulphate, 2-(cyclohexen-1′-yl) propionic acid (II) (a 3,4-unsaturated acid) was obtained (yield 98%), and with 97% sulphuric acid 2-(1′-hydroxycyclohexan-1′-yl) propionic acid lactone (III) was formed (93% yield). Several new γ-butyrolactones were obtained in good yield by this method.