Alkanoic adds

Considerable interest arose during the 1970 s and 1980 s in the use of micro-organisms to produce useful fatty adds and related compounds from hydrocarbons derived from the petroleum industry. During this period, a large number of patents were granted in Europe, USA and Japan protecting processes leading to the production of alkanols, alkyl oxides, ketones, alkanoic adds, alkane dioic acids and surfactants from hydrocarbons. Many of these processes involved the use of bacteria and yeasts associated with hydrocarbon catabolism. 

Resolution of branched alkanoic adds. Hydrolase-catalyzed esterification of 2-methylalkanoic acids can be fairly efficient, especially for acids with long chains, provided that the conditions are carefully adjusted by immobilization of the enzyme (in some cases), by control of the water activity, and by proper choice of the appropriate alcohol as nucleophile as well as the correct solvent [134]. The alcohol concentration does also influence the E-value [133]. It is important to note that the esterifications are reversible, thus preventing easy access to the remaining substrate in high ees. Some representative examples are given in Table 4.4. A procedure based on iterative resolutions can be used to provide both enantiomers of 2-methyloctanoic acid in high ees (>99%) and reasonable yields (25% for S- and 43% for R-acid based on the starting racemic acid) [137]. 

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