Microwave-Assisted Kinetic Resolution of Homochiral (Z)-Cyclooct-5-ene-1,2-diol and (Z)-2-Acetoxycyclooct-4-enyl Acetate Using Lipases

Abstract

Over the last decade, the use of biocatalysts has become an attractive alternative to conventional chemical methods, especially for organic synthesis, due to their unusual properties. Among these enzymes, lipases are the most widely used, because they are cheap, easily available, cofactor-free, and have broad substrate specificity. Combined to microwave heating in non-aqueous medium, recent results suggest that irradiation may influence the enzyme activity. This Communication reports the benefits of lipases and the microwave irradiation on the kinetic resolution of racemic homochiral (Z)-cyclooct-5-ene-1,2-diol and (Z)-2-acetoxycyclooct-4-enyl acetate. In order to best achieve the kinetic resolution, different parameters were studied including the type of lipase, the temperature, the impact of microwave power compared to conventional heating. Optimization of the reaction parameters lead to the obtainment of highly enriched or enantiopure diols and diesters in a clean, efficient and safe way.

Rapid Production of trans‐Cyclooctenes in Continuous Flow

“…Epoxide ( Z )‐ 9 was used for the synthesis of ( Z )‐ 2 without further purification. The 1 H NMR data were in accordance with published data …”

On the Effect of Microwave Energy on Lipase-Catalyzed Polycondensation Reactions

“…Most of the previous literature on CaLB and the use of MWe focuses on the processing of small molecules, such as kinetic resolutions of ( Z )-Cyclooct-5-ene-1,2-diol and ( Z )-2-Acetoxycyclooct-4-enyl acetate (Figure 1a) [21], biodiesel production [22], synthesis of small esters (Figure 1b) [23,24,25,26] and the characterization of the biocatalyst selectivities [27]. Despite extensive prior research into the use of biocatalysis for ester formation or reactions, only limited attempts have been made for the biocatalyzed synthesis of polyesters.…”