2-Hydroxy-4-alkoxybenzophenone derivs prepn - from 2,4-dihydroxybenzophenones and alkadiene, and used as UV stabilisers for polymers

摘要

Title cpds of formula (I): (where X = halogen, 1-8C alkyl, 1-4C alkoxy, 2-6C alkoxyalkyl or 6-8C aryl, R = H or CH3, Y = 1-8C alkyl, m = 0-2 and n = 0-1) are prepd. by reacting the corresp. 2, 4-di-hydroxybenzophenone cpd. with a diene of formula: CH2=C(R)-C(R)=CH2, in the presence of a Pd cpd. as catalyst and in suitable solvent (esp. a mixt. of an aromatic hydrocarbon and an N-substd. aliphatic amide in a vol. ratio of 0.5-10:1 esp. 1-5:1), and hydrogenating the prod. to give (I), (I) are ultra-violet stabilisers for synthetic and natural polymers e.g. polyethylene, PVC, polyamides, polyurethanes and cellulosic matls. and are used in amts. of 0.005-10(0.01-5) wt %. The use of expensive alkyl halides is avoided and a less-contaminated prod. is obtd. The catalysts used can be recovered.