GB817054A - Manufacture of esters - Google Patents

Abstract

Lubricating compositions contain, mixed with each other or with natural or synthetic hydrocarbon lubricants, esters of the formula <FORM:0817054/III/1> where R is a divalent hydrocarbon radical or an acyclic radical interrupted by at least one ether oxygen atom, R1 and R3 are C2-C4 alkylene and R2 and R4 are aliphatic hydrocarbon radicals other than methyl. Preferred compounds are those in which R is p-phenylene or octamethylene and R2COO and R4COO are derived from oleic acid. Aliphatic ethers can also be present in the compositions, especially ethers having more than 12 carbon atoms such as diethylhexyl ether. Various suitable esters are mentioned in which R is also tetramethylene, b - methyl - tetramethylene, 3:8 - dioxa - decamethylene and 4 - methyl - 3:7 - dioxa-nonamethylene; R1 and R3 can be ethylene or propylene (both isomers); R2 and R4 can also be ethyl, 3-heptyl or 2:4:4-trimethylpentyl.ALSO:The invention comprises (1) the preparation of esters of the formula R2-COO-R1-OOC-R-COO-R3-OOC-R4 where R is a divalent hydrocarbon radical or an acyclic radical interrupted by at least one ether oxygen atom, R1 and R3 are C2-C4 alkylene and R2 and R5 are aliphatic hydrocarbon radicals other than methyl by reacting alkali metal salts of R(COOH)2 with Hal-R1-OOC-R2 and/or Hal-R3-OOC-R4; (2) the preparation of the same esters by reacting Hal-R1-OOC-R-COO-R3-Hal with alkali metal salts of R2-COOH and/or R4-COOH; and (3) certain esters of the first formula above, viz. those in which R is an aromatic hydrocarbon radical and R2 and R4 have at least 14 carbon atoms and a single double bond which is non-terminal. The starting materials where R contains an ether group can be prepared by condensing a glycol (or reaction product with, e.g. propylene oxide) with an unsaturated nitrile and then hydrolysing. The halo-esters can be made by esterifying alkylene chlorhydrins or reacting alkylene oxides with carboxylic acid chlorides; the corresponding bromine, iodine and fluorine compounds can also be used. The halo-esters can then be mixed with the dicarboxylic acid, alkali carbonate added and the reaction completed by heating to 130-200 DEG C., preferably 140-170 DEG C. Examples show the reaction of (1) sodium terephthalate with oleic acid b -chloroethyl or b -chloroisopropyl ester and with heptane - 3 - carboxylic acid b - chloroethyl or b -chloropropyl ester; sodium adipate with oleic acid b -chloroethyl ester or heptane-3-carboxylic acid b -chloroethyl ester; sodium sebacate with oleic acid b -chloro-isopropyl ester or heptane-3-carboxylic acid b -chloropropyl ester; sodium salt of 1 : 3- or 1 : 4-bis-(b -carboxyethoxy)-butane with oleic acid b -chloroisopropyl ester; (2) adipic acid di-b -chloroethyl ester with sodium propionate, sodium heptane-3-carboxylate and sodium 2 : 2 : 4-trimethylpentene - 5 - carboxylate; b - methyladipic acid di-b -chloroethyl ester with sodium oleate and sodium heptane-3-carboxylate; b -methyladipic acid di-b -chloro-isopropyl ester with sodium oleate; sebacic acid di-b -chloroethyl ester with sodium heptane-3-carboxylate. Other specified starting materials are esters of propionic, butyric, 2 : 2 : 4 : 4 - tetramethylpentene - 1 - carboxylic, lauric, and palmitic acid and of soya bean fatty acids and the acids obtained in the oxidation of paraffin; the esters may be d -chlorobutyl or g -chloro-isobutyl in addition to the above. Oleic acid b -chloro-isopropyl ester is obtained from oleic acid chloride and propylene oxide. Sodium oleate is prepared from sodium carbonate and oleic acid in glycol at 120 DEG C. Specification 438,540, [Group IV], is referred to.