Patent GB-951935-A (GB)
Title: Tris phenolic compounds and their application
Inventor: RANSON DEREK
IPC: C07C37/20
Filed: 1960-04-14
Abstract: The invention comprises compounds in which three hydroxyphenyl groups are attached to a chain C-CH-CH, two of these groups being attached to the terminal CH group of the chain and each hydroxyphenyl group carrying at least two hydroxycarbon substituents, one at least of which is a tertiary group.  The other terminal carbon atom in the C-CH-CH chain is attached to hydrogen and (or) a substituent hydrocarbon radical or radicals, the chain being preferably part of an alkyl chain, which may be branched. The compounds are prepared by condensing a phenol, substituted as described above but having at least one free ortho- or para-position, with an a .b -unsaturated aldehyde having an unsubstituted a -carbon atom in the presence of an acidic condensing agent and an inert solvent.  In one example, 1 gr. mol. of crotonaldehyde is condensed with 3 gr. mols. of 3-methyl-6-tert.-butylphenol in methanol or glacial acetic acid and in the presence of concentrated hydrochloric acid, to yield a product to which the formula <FORM:0951935/C2/1> is assigned; the acetyl and benzoyl derivatives of the product are described.  In other examples cinnamaldehyde and acrolein are condensed with 3-methyl-6-tert.-butylphenol under similar conditions.  Zinc chloride, sulphuric acid and fluorosulphonic acid are other specified condensing agents.  Another specified phenol is 3-methyl-6-(a ,a ,g ,g -tetramethylbutyl) phenol. The products are useful as antioxidants, particularly for polyethylene, polypropylene, ester polymers and natural or synthetic rubbers, and experimental results relating to these applications are given.ALSO:The invention comprises compounds in which three hydroxyphenyl groups are attached to a chain C-CH-CH, two of these groups being attached to the terminal CH group of the chain and each hydroxyphenyl group carrying at least two hydrocarbon substituents, one at least of which is a tertiary group. The other terminal carbon atom in the C-CH-CH chain is attached to hydrogen and (or) a substituent hydrocarbon radical or radicals, the chain being preferably part of an alkyl chain, which may be branched. The compounds are prepared by condensing a phenol, substituted as described above but having at least one free ortho- or para-position, with an a , b -unsaturated aldehyde having an unsubstituted a -carbon atom in the presence of an acidic condensing agent and an inert solvent. In one example, 1 gr. mol. of crotonaldehyde is condensed with 3 gr. mols. of 3-methyl-6-tert.-butylphenol in methanol or glacial acetic acid and in the presence of concentrated hydrochloric acid to yield a product to which the formula <FORM:0951935/C3/1> is assigned. In other examples cinnamaldehyde and acrolein are condensed with 3-methyl-6-tert.-butylphenol under similar conditions. Another specified phenol is 3-methyl-6-(a , a , g , g -tetramethylbutyl) phenol. The products are useful as antioxidants, particularly for polyethylene, polypropylene, ester polymers (e.g. polyethylene terephthalate) and natural or synthetic rubbers, and experimental results relating to these applications are given.