Programing a cyanide-free transformation of aldehydes to nitriles and one-pot synthesis of amides through tandem chemo-enzymatic cascades

Abstract

A chemo-enzymatic cascade was developed for the cyanide-free synthesis of nitriles from aldehydes and further one-pot transformation into amides.

Kinetic model of asymmetric dehydration of aldoxime catalyzed by immobilized OxdPsp in an organic solvent

“…32 In a biphasic reaction system, nitriles and corresponding amides were prepared starting from aldoxime via aldoxime dehydration and nitrile hydration catalyzed sequentially by OxdF1 and nitrile hydratase with an isolation yield of approximately 62%. 33 The reaction starts with the oxidation of alcohols to aldehydes by sodium hypochlorite, and their subsequent condensation with hydroxylamine toward aldoximes. After separation, the aldoxime was dehydrated by OxdB to prepare nitriles with yields of up to 70%.…”

Enantiodivergent Functionalization of Aryl Alkenes into Diverse Biarylalkanoic Acids by Integrating Biocatalytic Cascades with Chemocatalysis

“…Improvement could be achieved by using membrane compartmentalization, 46,47 cross-linked enzyme aggregates (CLEAs), 48 and biphasic solvent systems. 49,50 We opted for a simple operation by heating and centrifuging the biotransformation mixture to remove cells and proteins. Using this treatment, similar conversion and ee could be achieved with lower Pd catalyst loading (5 mol %) and higher substrate loading (10 mM) (Figure 3b, entries 2 and 3).…”

“…In the cross-coupling reaction, some deactivation of Pd catalyst by biotransformation components, such as cell debris and proteins, was observed, likely due to their ability to coordinate to the metal catalyst (Table S2). Improvement could be achieved by using membrane compartmentalization, , cross-linked enzyme aggregates (CLEAs), and biphasic solvent systems. , We opted for a simple operation by heating and centrifuging the biotransformation mixture to remove cells and proteins. Using this treatment, similar conversion and ee could be achieved with lower Pd catalyst loading (5 mol %) and higher substrate loading (10 mM) (Figure b, entries 2 and 3).…”

Enzyme Anchoring Amphiphilic Polymer Nanoparticles for Enhanced Pickering Interfacial Biocatalysis

“…In recent years, during the process of pursuing a greener industry, biocatalysis has attracted increasing focus as it can enhance reaction efficiency and selectivity while reducing pollution. − As a result, enzymes have been introduced into various reaction systems − including organic–aqueous biphasic systems − (hereafter called biphasic systems). However, if enzymes are simply combined with biphasic systems, the reaction performance is usually unsatisfactory since the reaction rate of biphasic systems is normally limited by the slow rate of mass transfer. − On the other hand, dissolved enzymes are hard to be separated from reaction systems, which may affect the product quality.…”