Patent GB-996502-A (GB)
Title: Esters containing an alkylhydroxyphenyl group and stabilisation of organic material therewith
IPC: C07C69/66
Filed: 1962-10-26
Abstract: The invention relates to compounds of the formula <FORM:0996502/C2/1> wherein A is a straight-chain or branched-chain alkylene radical, m is 0 or 1, R1 and R2 are each independently alkyl radicals having 1 to 6 carbon atoms; R is alkyl having from 2 to 18 carbon atoms, alkylthioalkylene having from 3 to 18 carbon atoms, and hydroxyalkyl thioalkylene having at least 4 carbon atoms, or the radical <FORM:0996502/C2/2> in which B is a straight- or branched-chain alkylene; R1 and R2 are each independently alkyl radicals having 1 to 6 carbon atoms; m and n are each independently 0 or 1; and X is sulphur or oxygen. Specified compounds are methyl 3,5-di-t-butyl - 4 - hydroxyphenylacetate, n - octadecyl 3,5 - di - t - butyl - 4 - hydroxyphenyl - acetate; n - octadecyl 3,5 - di - t - butyl - 4 - hydroxybenzoate; n - octadecyl - b - (3,5 - di - t - butyl - 4 - hydroxyphenyl) - propionate; 2 - (n - octylthio - ethyl) 3,5 - di - t - butyl - 4 - hydroxybenzoate; 2 - (n - octylthio - ethyl), 3,5 - di - t-butyl - 4 - hydroxy - phenylacetate; 2 - (n-octadecylthioethyl) 3,5 - di - t - butyl - 4 - hydroxyphenylacetate; 2 - (n - octadecylthioethyl), 3,5 - di - t - butyl - 4 - hydroxybenzoate; 2 - hydroxyethylthio - 21 - ethyl (3,5 - di - t - butyl - 4 - hydroxy) benzoate; b ,b 1 - thiodiethyl bis - (3,5 - di - t - butyl - 4 - hydroxyphenylacetate; n - hexyl 3,5 - di - t - butyl - 4 - hydroxybenzoate; n - dodecyl 3,5 - di - t - butyl - 4 - hydrobenzoate; diethylene glycol bis-[3-(3,5 - di - t - butyl - 4 - hydroxyphenyl propionate]; 1,2 - propylene glycol bis - [3 - 3,5 - di - t - butyl - 4 - hydroxyphenyl) propionate]; ethylene glycol bis - [3 - (3,5 - di - t - butyl - 4 - hydroxyphenyl) propionate]. Compounds may be prepared according to the following reactions R1(CH2)nCOOR2+R3OH-->R1 (CH2)nCOOR3 R1(CH2)nCOCl+R3OH -->R1(CH2 nCOOR3 <FORM:0996502/C2/3> where R1 is an hydroxyphenyl mono- or di-alkyl-substituted radical; R2 is hydrogen or alkyl; R3 is alkyl; R4 is alkylene, isoalkylene etc.; and n is 0, 1, 2 &c. In an example, methyl 3,5-di-t-butyl-4-hydroxy-phenylacetate is produced by reacting 3,5-di-t-butyl-4-hydroxyphenyl acetic acid and methanol in the presence of p-toluenesulphonic acid. In another example, n-octadecyl, 3,5-di-t-butyl-4-hydroxybenzoate is produced by reacting methyl 3,5 - di - t - butyl - 4 - hydroxybenzoate and n-octadecyl alcohol, the benzoate being produced by reacting 2,6-di-t-butylphenol in methanol and sodium hydroxide with carbon tetrachloride. In another example, 2-(n-octylthioethyl) 3,5 - di - t - butyl - 4 - hydroxybenzoate is produced by reacting 3,5-di-t-butyl-4-hydroxybenzoic acid in methanol with 2-chloroethyl - n - octyl sulphide. In another example, b ,b 1 - thiodiethyl bis - (3,5 - di - t - butyl - 4 - hydroxy - phenylacetate is produced by reacting b ,b 1-dihydroxydiethyl sulphide with methyl 3,5 - di - t - butyl - 4 - hydroxyphenyl-acetate. In another example, diethylene glycol bis - [3 - (3,5 - di - t - butyl - 4 - hydroxyphenyl) propionate) is produced by reacting 3-(3,5 - di - t - butyl - 4 - hydroxyphenyl) - propionic acid and diethylene glycol in the presence of para-toluene sulphonic acid monohydrate. In another example, 1,2-propylene glycol bis - [3 - (3,5 - di - t - butyl - 4 - hydroxyphenyl) propionate] is produced by reacting 3-(3,5-di - t - butyl - 4 - hydroxyphenyl) propionic acid with propylene glycol in the presence of para-toluene sulphonic acid monohydrate.ALSO:Polypropylene and polystyrene resin containing an elastomer (i.e. butadiene-styrene) are stabilized by incorporating a stabilizer of a general formula <FORM:0996502/C3/1> wherein A is a straight-chain or branched-chain alkylene radical, m is 0 or 1, R1 and R2 are each independently alkyl radicals having 1 to 6 carbon atoms, R is alkyl having from 2 to 18 carbon atoms, alkylthio-alkylene having from 3 to 18 carbon atoms, hydroxyalkylthioalkylene having at least 4 carbon atoms, or the radical <FORM:0996502/C3/2> in which B is a straight- or branched-chain alkylene, R1 and R2 are each independently alkyl radicals having 1 to 6 carbon atoms, m and n are each independently 0 or 1, and X is sulfur or oxygen, for example 2-(n-octadecylthioethyl) 3,5 - di - t - butyl - 4 - hydroxyphenylacetate; n - octadecyl 3,5 - di - t - butyl - 4 - hydroxybenzoate; n - octadecyl b - (3,5 - di - t - butyl-4-hydroxyphenyl) propionate and 2 - (n - octylthioethyl) 3,5 - di - t - butyl - 4 - hydroxybenzoate.ALSO:Mineral oil is stabilized by incorporating a stabilizer of the general formula <FORM:0996502/C4-C5/1> wherein A is a straight-chain or branched-chain alkylene radical, m is 0 or 1, R1 and R2 are each independently alkyl radicals having 1 to 6 carbon atoms, R is alkyl having from 2 to 18 carbon atoms, alkylthio-alkylene having from 3 to 18 carbon atoms, hydroxyalkylthioalkylene having at least 4 carbon atoms, or the radical <FORM:0996502/C4-C5/2> in which B is a straight- or branched-chain alkylene, R1 and R2 are each independently alkyl radicals having 1 to 6 carbon atoms, m and n are each independently 0 or 1, and X is sulfur or oxygen, for example n-octadecyl-3,5-di-t-butyl -4-hydroxyphenylacetate.