A green method for alkene epoxidation based on the chemo-enzymatic perhydrolysis of carboxylic acids and esters has been optimized using Novozyme 435, the immobilized form of Candida antarctica lipase B, and the complex urea-hydrogen peroxide (UHP). UHP, an anhydrous form of hydrogen peroxide, has the potential of releasing hydrogen peroxide in a controlled manner and thus avoids the need to add the aqueous hydrogen peroxide slowly to the reaction mixture. The absence of water in the reaction media was also beneficial, because it minimized undesired reactions of the oxidized products. A minimum amount of enzyme was necessary to show the catalytic effect. On recycling, the enzyme maintained its activity up to six rounds of epoxidations. A range of alkenes was epoxidized by this method providing yields ranging from 75 to 100 percent.

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A green method for Baeyer-Villiger oxidation based on the chemo-enzymatic perhydrolysis of carboxylic acids and esters has been optimized using Novozyme-435, the immobilized form of Candida antarctica lipase B, and the complex urea-hydrogen peroxide (UHP) in ethyl acetate. This protocol previously employed for the chemo-enzymatic epoxidation of unfunctionalized olefins was shown to be effective for the Baeyer-Villiger oxidation of cyclohexanone and substituted cyclohexanones. The absence of water in the reaction media avoided any hydrolysis of the oxidized product. A minimum amount of enzyme was necessary to show the catalytic effect. The reaction yields of substituted e-caprolactones varied depending on the nature of the substituent.

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Oxidation of halogenated benzenes with bacterial dioxygenase from Pseudomonas putida 39D (whole cell fermentation) provided homochirall,3-cyclohexadiene-cis-diols 1 for the entire halogen series. These compounds were investigated for their potential in cycloadditions with various dienophiles including propiolate, acylnitroso compounds, benzyne, quinones, and nitrile oxides. All cycloadducts formed with the regiochemistry predicted from molecular modeling. A brief synthesis of (+)-lycoricidine concluded the application of acylnitroso cycloadditions. New adducts of quinones and nitrile oxides were identified, and potential for these compounds in the synthesis of novel polycyclic oxygenated compounds is indicated. Experimental and spectral data are provided for all compounds.