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Abstract:The tandem use of laccases and lipases has been exploited for the simple preparative synthesis of enantiomerically enriched dimeric phenols. Laccase-catalyzed oxidation of isoeugenol (1) and vinylguaiacol (7) in biphasic systems gave as main products the racemic compounds 6 and 8, possessing structures similar to the b-5 dimers found in lignin. The synthesis of enantiomerically enriched 6 and 8 could be achieved by alcoholysis reactions catalyzed by commercial preparations of lipases in organic solvents. Although the E values were quite low (due to the "remote" stereocenters to be discriminated), the enantio-complementary behavior of the tested lipases allowed the simple isolation of the target compounds with ee up to 90%. It is noteworthy that these results have been achieved in vitro exploiting commercially available enzymes, without using the so-called "dirigent" proteins evolved by nature to direct the enantioselective coupling of phenols in vivo.

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A simple chemoenzymatic strategy for the synthesis of colored and fluorescent poly(ε‐caprolactone) esters has been developed. The procedure involves first the reaction of a functionalized primary amine with ε‐caprolactone, to give an amide with a terminal primary hydroxy group, followed by an enzymatic ring‐opening polymerization catalyzed by Novozym 435. The proposed method is easy to handle and is suitable for the incorporation of different amines, as it shown for the yellow compound N‐deacetylthiocolchicine and the fluorescent amines 4‐(2‐aminoethylamino)‐7‐(N,N‐dimethylsulfamoyl)benzofurazan and dansylcadaverine. A similar strategy is considered for the synthesis of poly(ε‐caprolactone) esters, employing alcohols as initiators of the reaction. In this case, an intermediate ester carrying a terminal primary hydroxy group cannot be isolated and the reaction forms directly the desired polymers.