Preparation of optically active aliphatic carboxylic acids

Abstract From the Canadian patent

An improved process for the separation of enantiomers of a racemic mixture of certain aliphatic carboxylic acids or esters thereof is disclosed. The process involves: (i) forming a salt solution comprising said racemic mixture of a C1 to C6 linear or branched aliphatic carboxylic acid and an organic or inorganic base; (ii) treating said salt solution with one-half molar equivalent of a chiral organic nitrogenous base having a base strength no stronger than said organic or inorganic base; and (iii) precipitating from the reaction solution formed in step (ii) the less soluble diastereomeric salt, the improvement being adding to the salt solultion of step (ii) an inert organic or inorganic …