Abstract:
Liquid hydrocarbon motor fuels, which may or may not be leaded, comprise a cyclic di-ester of an alkane-diol having 2-8 carbon atoms with an alkyl-boronic acid having 6-10 carbon atoms, in an amount sufficient to diminish the octane requirement increase of an internal combustion engine in which the fuel is used, generally an amount equivalent to 0.0002 to 0.02 per cent by weight of boron. The fuels may also comprise anti-oxidants, gum inhibitors, solvent oils, upper cylinder lubricants, dyes and perfumes. Examples illustrate the use in iso-octane and a leaded gasoline of esters of n-hexyl and n-octyl boronic acids with ethylene glycol, propylene glycol, 2 : 5-hexanediol, 2 : 3 - dimethyl - 2 : 3 - butanediol, 2-methyl - 2 : 4 - pentanediol or 2 : 2 - diethyl propanediol. The preparation of the esters is given (see Group IV (b)). Specifications 722,537 and 773,169 are referred to.ALSO:The invention comprises cyclic di-esters of alkane-diols having 2-8 carbon atoms with alkyl boronic acids having 6-10 carbon atoms which may be prepared by reacting the diol with the acid, preferably by refluxing approximately equimolecular proportions thereof in an inert medium such as an aromatic hydrocarbon, e.g. benzene, with azeotropic removal of the water formed. Examples describe the preparation of the cyclic diesters of n-octyl boronic acid with 2-methyl-2,4-pentanediol, 2 : 5 - hexanediol, 2,3 - dimethyl - 2,3 - butane-diol and 2,2-diethyl propanediol and of n-hexyl boronic acid with those diols and also with ethylene and propylene glycols. The esters may be used as additives in motor fuels (see Group III). Specifications 722,537, [Group III], and 773,169 are referred to.