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

Abstract

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.