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| Optically active silicon containing cyanohydrin: (R)-2-trimethylsilyl-2-hydroxyl- propionitrile was successfully synthesized by asymmetric transcyanation of acetyltrimethylsilane with acetone cyanohydrin in an aqueous/organic biphasic system catalyzed with (R)-oxynitrilase from defatted Prunus Japonica seed meal. Various influential variables were examined for better understanding of the reaction. Diisopropyl ether was found to be the best organic phase for the reaction among all the organic solvents explored. The optimum concentrations of acetyltrimethylsilane and acetone cyanohydrin, volume ratio of aqueous phase to organic phase, buffer pH value and the reaction temperature were 14 mmol ∙ L–1, 28 mmol ∙ L–1, 13% (by volume), 5.0 and 30 oC, respectively. Under the above optimal conditions, the initial reaction rate, the substrate conversion and the product enantiomeric excess were 1.34 mmol∙L–1 ∙ h–1, 99.0% and 99.0%, respectively. |
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| Keywords:(R)-oxynitrilase; asymmetric transcyanation; acetyltrimethylsilane; (R)-2-trimethylsilyl-2-hydroxyl-propionitrile |
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