Aliphatic dicarboxylic acid prepn. from cyclomonoalkenes - by reaction with aliphatic dicarboxylic acids and oxidn. of cycloalkyl esters

摘要

Aliphatic 5-12C dicarboxylic acids (I) are prepd. by (i) reacting a 5-12C cyclomonoalkene (II) with a 4-12C aliphatic dicarboxylic acid (III), in the presence of an acid catalyst, pref. at 80-180 degrees C, and (ii) oxidising the obtd. cycloalkyl esters of (III) with HNO3, pref. at 40-120 degrees C. (I) are starting materials for prodn. of synthetic fibres, plastic compsns. and plasticisers. (II) are cheap and easily available. (III) are not lost during oxidn. and can be recycled. Acid catalyst for esterification in (i) may be H2SO4, a sulphonic acid or a cation exchanger resin, esp. contg. acid gps. in which H atoms are partly replaced by metal ions. Oxidn. catalyst in (ii) may be a combination of soluble V- and soluble Cu cpds.