GB655608A - Antioxidants comprising seleno fatty acids, salts or esters thereof - Google Patents

Abstract

Compounds of general formula <FORM:0655608/IV (a)/1> and salts and esters thereof in which a and b are whole numbers, c and d are whole numbers including zero, m is 1 or 2 and a+c and b+d are 7-21 and compounds of general formula <FORM:0655608/IV (a)/2> and salts and esters thereof in which m is 1 or 2 and a and b are at least 7 are stabilizers for polypropylenes and polybutenes. For the preparation of the compounds (see Group IV (b) Abridgment). The Specification as open to inspection under Sect. 91 states that the compounds may be substituted with other groups, tellurium may replace selenium in the first formula and a, b, c and d are not limited as above. This subject-matter does not appear in the Specification as accepted.ALSO:Selenium compounds are made by treating a C10 to C24 unsaturated fatty acid or salt or ester thereof with the unsaturated group at least one carbon atom away from the carboxyl group with a hydrogen halide to produce the corresponding halo compound with the halogen attached to one of the carbon atoms forming the unsaturated group of the parent material and treating two mols. of this compound with one mol. of a metal selenide or diselenide. Selenium compounds are also made by halogenating the alpha carbon atom of a saturated fatty acid containing not less than 10 carbon atoms in the molecule and treating two mols. of this compound with one mol. of a metal selenide or diselenide. Many acids to be treated are specified including lauric, stearic, oleic, behenic, elaidic, rapic and palmitoleic acids. Hydrogen bromide, chloride and iodide are specified hydrogen halides and iodine, bromine and chlorine specified halogens. Sodium and potassium selenide and diselenide are specified selenides. Esters may be alkyl, aryl, aralkyl or cycloalkyl, methyl, ethyl and propyl groups being specified. When the free fatty acids are used in the preparation the acids obtained may be converted by conventional methods into their salts, esters and anhydrides, amides and acyl chlorides, and similarly esters may be converted to acids and salts to esters, acids or other salts, e.g. the sodium salts dispersed or dissolved in water or aqueous alcohol may be treated with a solution of a polyvalent metal salt such as zinc acetate or calcium or barium chloride. The compounds are added to oxidizable essentially hydrocarbon substances and possess antioxidant, anticorrosive and detergent properties. They may be used with other additions, many of which are specified including calcium and barium salts of alkylaryl sulphonic acids obtainable by alkylating benzene with cetyl chloride, chlorinated kerosene or white oil and sulphonating the product. In examples: (1) oleic acid is reacted with hydrogen bromide in glacial acetic acid, the brominated acid thus obtained converted to its sodium salt with sodium hydroxide and refluxed with sodium selenide in ethyl alcohol, the required 1,11-dicarboxy 8,81- (or 9,91-) heptadecyl selenide being obtained on acidification of the reaction mixture; (2) the selenide of (1) is esterified by refluxing in ethyl alcohol containing hydrogen chloride; (3) the zinc salt of the selenide of (1) is made by treating the monosodium salt thereof dissolved in aqueous alcohol aith zinc acetate dissolved in the same solvent, and in (4) palmitic acid is treated with bromine in the presence of red phosphorus and the alpha bromo palmitic acid isolated and esterified by treatment with ethyl alcohol and hydrogen chloride when the product is refluxed with sodium selenide in ethyl alcohol to produce 1,11-dicarboethoxy-1,11-dipentadecyl selenide. It is stated that the sodium and normal calcium, barium and zinc salts and the methyl, ethyl and propyl esters of 1,11-dicarboxy-1,11-duindecyl and 1,11-dicarboxy-1,11-dipentacosyl selenides may be made by chlorinating lauric and cerotic acids in the alpha position and treating the products with sodium selenide to obtain the above selenides which may then be converted to their salts or esters. In the Specification as open to inspection under Sect. 91, tellurium may replace selenium in compounds obtained from unsaturated fatty acids, hydrogen atoms of the fatty acids may be substituted with other groups and acids other than the above are specified, e.g. acrylic, vinyl acetic, propionic and valeric acids. The compounds are stated to be stabilizers for aldehydes and ketones and other oxidizable organic substances. This subject-matter does not appear in the Specification as accepted.ALSO:Compounds of general formula <FORM:0655608/III/1> and salts and esters thereof, wherein a and b are whole numbers, c and d are whole numbers including zero, m is 1 or 2 and a+c and b+d are 7-21, and compounds of general formula <FORM:0655608/III/2> and salts and esters thereof in which m is 1 or 2 and a and b are at least 7, are added to hydrocarbon oils. They possess antioxidant, anticorrosive and detergent properties and are prepared as indicated in the Group IV (b) Abridgment. Oils specified are mineral lubricating oils, e.g. paraffinic, naphthenic or mixed base stocks from spindle oils to heavy cylinder stocks, and kerosene. Preferred compounds are the free acids of the first formula, their esters and divalent metal salts. Preferred are monoselenides. As rust inhibitors for turbine oils free acids are preferred, as antioxidants esters are preferred, polyvalent metal salt derivatives are preferred for the prevention of piston-ring sticking. Addition from fatty acids having the unsaturated group far removed from the carboxyl group (as in the 6, 7 position, or farther away), are preferred to those in which the unsaturated group is closer. They may be used in conjunction with known additives, many of which are specified. A stock solution containing, e.g., 2-5 per cent by weight of compound in hydrocarbon lubricating oil may be prepared and the compounds are effective in amounts of 0.1-2 per cent, preferably 0.5-1.5 per cent, by weight, based on finished oil. In example (5) white oil of medicinal grade containing 1,11-dicarboxy-8,81- (or 9,91-) diheptadecyl selenide or its diethyl ester or zinc salt or 1,11 - dicarbethoxy - 1,11 - dipentadecyl selenide in amounts providing 0.019 per cent of selenium are treated with oxygen at 340 DEG F. and results compared with the white oil without additive and piston discoloration results are given for a Lauson engine test in a base oil containing the zinc salt of 1,11-dicarboxy-8,81- (or 9,91-) diheptadecyl selenide and calcium alkyl phenite and for a Wisconsin engine test on a base oil containing 1,11 - dicarbethoxy - 8,81 - (or 9,91 ) dipentadecyl selenide and barium metacetoxy phenate in both tests, the treated oils are used as crank - case lubricants. Specification 538,474 and U.S.A. Specifications 2,252,984, 2,261,047, 2,360,302 and 2,398,415 are referred to. The Specification as open to inspection under Sect. 91 states that the compounds may be substituted with other groups, selenium of the first formula may be replaced by tellurium, and a, b, c and d would not appear to be limited as above. This subject-matter does not appear in the Specification as accepted.ALSO:Compounds of general formula <FORM:0655608/V/1> and salts and esters thereof wherein a and b are whole numbers, c and d are whole numbers including zero, m is 1 or 2 and a+c and b+d are 7-21, and compounds of general formula <FORM:0655608/V/2> and salts and esters thereof, in which m is 1 or 2 and a and b are at least 7, are stabilizers for rubber. For the preparation of these compounds (see Group IV (b) Abridgment). The Specification as open to inspection under Sect. 91 states that the compounds may be substituted with other groups, tellurium may replace selenium in the first formula and a, b, c and d would not appear to be limited as above. This subject-matter does not appear in the Specification as accepted.