Solubility of epoxides

The bioeatalytie resolution of epoxides has mainly been performed in single aqueous buffer systems. In our laboratory, B/nEH has been proved to be very useful for ehiral synthesis of (i )-GPE on a preparative scale. More importantly, this enzyme exhibited a eomplementary enantiospecificity as compared with those deseribed so far, affording the unreacted epoxide in (S)-configuration which is the solely useful enantiomer for synthesis of bioactive p-blockers. In a single aqueous phase, however, most epoxides including GPE may be spontaneously hydrolyzed into vicinal diols without any enantiospecificity. In addition, only at a very low concentration can epoxides be dissolved in aqueous media. The instability and low solubility of epoxides in the aqueous phase may result in a remarkable decrease in the yield of kinetic resolutions, thus limiting the application of these resolution processes on a practical scale. 

Overall, epoxide hydrolases are very important enzymes for the as5mimetric synthesis of optically pure epoxides and 1,2-diols. The biphasic application of EHs and the development of continuous processes have made them industrially attractive In spite of that, thdr application in synthetic chemistry is still limited due to low regioselectivity, chemical instability, low solubility of epoxides in water and awiilable alternative chemical routes. Nevertheless, it is important to exploit and investigate new epoxide hydrolases for synthetic routes to chiral epoxides and diols. 

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