This work deals with the resolution of DL-menthol with propionic acid by Candida cylindracea lipase (Ccl) in organic solvent reaction systems and a reverse micelles system of sodium 1,4-bis (2-ethylhexyl) sulfosuccinate (AOT). The activity and stability as well as enantioselectivity of the lipase in two systems were studied. The results indicate that the lipase showed higher stability in reverse micelles than in organic solvent, which proved that the reverse micelles system has potential application for maintaining the activity of the enzyme for a long time. This is because lipase molecules can be entrapped in water-containing micro-drops of reverse micelles, avoiding direct-contract with unfavorable organic medium. The enantioselectivity (E > 30, ee p = 92.5) in the two systems is relatively high, although the conversion is moderate. The influence of the characteristic parameters of the two systems, such as pH, temperature, w 0 (molar ratio of water to AOT in reverse micelles systems) and water content (organic solvent) on the conversion of DL-menthol was also investigated.

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2008 C-C bond formation O 0282 Calix[n]arene Sulfonic Acids Bearing Pendant Aliphatic Chains as Recyclable Surfactant-Type Broensted Acid Catalysts for Allylic Alkylation with Allyl Alcohols inWater. -Calix[n]arene sulfonic acids bearing aliphatic chains are highly efficient for allylic alkylation reactions. The catalyst can be recovered from an aqueous reaction system and reused many times without significant loss of activity. -(LIU, Y.-L.; LIU*, L.; WANG, Y.-L.; HAN, Y.-C.; WANG, D.; CHEN, Y.-J.; Green Chem.