Enzymatic Cleavage of Aryl Acetates. Issue 17 (16th August 2016)

• Record Type: Journal Article
• Authors: Bauch, Marcel; Böttcher, Dominique; Bornscheuer, Uwe T.; Linker, Torsten
• Is Part Of: ChemCatChem. Volume 8:Issue 17(2016)
• Page Start: 2853
• Page End: 2857
• Publication Date: 2016-08-16
• Subjects: arenes -- enzyme catalysis -- regioselectivity -- steric hindrance -- substituent effects; Catalysis -- Periodicals; 541.39505
• DOI: 10.1002/cctc.201600678
• Languages: English
• ISSNs: 1867-3880

Abstract

Abstract: Seven enzymes have been screened for the cleavage of aryl acetates. Phenyl and naphthyl acetates react with lipases and esterases, whereas the sterically demanding anthracene acetate gave a conversion only with porcine liver esterase and esterase 2 from Bacillus subtilis (BS2) . These two enzymes have been employed on a preparative (0.5 mmol) scale and afforded cleavage products in 91 and 94 % yields, even for anthracene acetate. Thus, this method is superior to chemical cleavage with catalytic amounts of sodium methoxide (Zemplén conditions), which gave only low conversions. Finally, regioselectivity has been achieved with an anthracene bisacetate, in which an ethyl group controls the cleavage of the first acetate. This indicates that steric interactions play a crucial role in the enzymatic cleavage of aryl acetates, which might be interesting for future applications or the development of enzyme inhibitors. Abstract : Size matters : Although phenyl and naphthyl esters react smoothly with lipases and esterases, sterically demanding anthracene acetate was hitherto inert towards enzymatic cleavage. Herein we describe esterase 2 from Bacillus subtilis (BS2) as a suitable catalyst for such substrates on an analytical and preparative scale. In contrast, the use of sodium methoxide (Zemplén conditions) as the catalyst gives only incomplete conversions.