Nachwuchsgruppe für Mikrobielle Biotechnologie, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780, Bochum, Germany.
Lehrstuhl für Organische Chemie I, Fakultät für Chemie, Universität Bielefeld, Universitätsstrasse 25, 33615, Bielefeld, Germany.
Angew Chem Int Ed Engl. 2016 Nov 14;55(47):14823-14827. doi: 10.1002/anie.201607777. Epub 2016 Oct 18.
The combination of enzymes with traditional chemical catalysts unifies the high selectivity of the former with the versatility of the latter. A major challenge of this approach is the difference in the optimal reaction conditions for each catalyst type. In this work, we combined a cofactor-free decarboxylase with a ruthenium metathesis catalyst to produce high-value antioxidants from bio-based precursors. As suitable ruthenium catalysts did not show satisfactory activity under aqueous conditions, the reaction required the use of an organic solvent, which in turn significantly reduced enzyme activity. Upon encapsulation of the decarboxylase in a cryogel, the decarboxylation could be conducted in an organic solvent, and the recovery of the enzyme after the reaction was facilitated. After an intermediate drying step, the subsequent metathesis in pure organic solvent proved to be straightforward. The synthetic utility of the cascade was demonstrated by the synthesis of the antioxidant 4,4'-dihydroxystilbene in an overall yield of 90 %.
酶与传统化学催化剂的结合将前者的高选择性与后者的多功能性结合在一起。这种方法的主要挑战是每种催化剂类型的最佳反应条件不同。在这项工作中，我们将一种无辅因子脱羧酶与钌复分解催化剂结合在一起，从基于生物的前体物中生产高价值的抗氧化剂。由于合适的钌催化剂在水相条件下没有表现出令人满意的活性，因此反应需要使用有机溶剂，这反过来又显著降低了酶的活性。通过将脱羧酶封装在冰晶中，可以在有机溶剂中进行脱羧反应，并且反应后有利于酶的回收。经过中间干燥步骤后，随后在纯有机溶剂中的复分解反应证明是简单的。通过合成抗氧化剂 4,4'-二羟基二苯乙烯，总收率为 90%，证明了级联反应的合成实用性。
