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The Baeyer-Villiger monooxygenase (BVMO) 'MO14' from Rhodococcus jostii RHA1, is an enantioselective BVMO that catalyses the resolution of the model ketone substrate bicyclo[3.2.0]hept-2-en-6-one to the (1S,5R)-2-oxa lactone and the residual (1S,5R)-substrate enantiomer. This regio-plus enantioselective behaviour is highly unusual for BVMOs, which often perform enantiodivergent biotransformations of this substrate. The scaleability of the transformation was investigated using fermentor-based experiments, in which variables including gene codon optimisation, temperature and substrate concentration were investigated. E. coli cells expressing MO14 catalysed the resolution of bicyclo[3.2.0]hept-2-en-6-one to yield (1S,5R)-2-oxa lactone of >99% ee and (1S,5R)-ketone of 96% ee after 14 h at a temperature of 16 °C and a substrate concentration of 0.5 g L(-1) (4.5 mM). MO14 is thus a promising biocatalyst for the production of enantio-enriched ketones and lactones derived from the [3.2.0] platform.

Total and partial rate factors for the phenylation of some para-disubstituted derivatives of benzene have been obtained by means of competitive reactions in which benzoyl peroxide has been allowed to decompose in equimolar mixtures of the para-disubstituted derivative of benzene and para-dichlorobenzene. Nitrobenzene was also used as standard in a few cases. When both groups in a para-disubstituted benzene have similar electronic properties their effect on reactivity is additive compared with that of the two monosubstituted benzenes having the same groups. When the two groups have opposite electronic properties the reactivity is lowered below that of the more reactive of the corresponding two monosubstituted benzenes. Revised figures are reported for total and partial rate factors for some monosubstituted benzenes.