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The back cover of the journal long with the review of the article "Towards environmentally acceptable synthesis of chiral α-hydroxy ketones via oxidase-lyase cascades" by Dr Sandy Schmidt, and Dr Frank Hollmann published in the journal "Green Chemistry" is presented.

An aqueous chemoenzymatic cascade reaction combining Pd-catalyzed C–C formation and enzymatic C＝C asymmetric hydrogenation (AH) was developed for enantioselective synthesis of tertiary α-aryl cycloketones in good yields and excellent enantioselectivities. The stereopreference of the enzyme in AH of α-aryl cyclohexenones was studied. An enantiocomplementary enzyme was obtained by site-directed mutation. [ABSTRACT FROM AUTHOR]

In general, hydrogen peroxide is a stable and relatively mild oxidant and it can be regarded as the ultimate “green” reagent because water and oxygen are the only by-products. Besides the direct application of H2O2 in chemical processes more and more enzymatic syntheses based on hydrogen peroxide were developed. Different types of reactions can be addressed by using a hydrogen-peroxide driven biocatalysis (e.g. hydroxylations, epoxidations, sulfoxidations, halogenations, Baeyer–Villiger oxidations, decarboxylations). H2O2-driven reactions can often be used to substitute NAD(P)H dependent reactions. Therefore, laborious cofactor regeneration systems can be avoided by using H2O2-dependent enzymes. The tremendous increase in the number of publications dealing with this type of reactions clearly demonstrates the progress in this area in recent years. The described innovations range from new enzymes and types of reaction to novel reaction engineering approaches. This review aims to give the scope of possible advantageous applications of peroxyzymes and a critical discussion of their current limitations. The versatile reactions, the ecological advantageous and the great progress in the discovery and engineering of novel enzymes make a technical use feasible. [ABSTRACT FROM AUTHOR]

Carbon-nanodot-doped g-C3N4 is used as a photocatalyst to promote the aerobic oxidation of alcohols and oxyfunctionalisation of activated hydrocarbons. A critical E-factor analysis of the current reaction system reveals its limitations en route to environmentally acceptable oxidation procedures. [ABSTRACT FROM AUTHOR]

The table of contents of the journal is presented along with the issue's editors and information on advisory board and authors.

The one-pot multistep enzymatic oxidation of aliphatic and benzylic alcohols to the corresponding aldehydes combined with their subsequent carboligation to chiral α-hydroxy ketones has been exemplarily evaluated in terms of being a “green” biocatalytic approach. Besides the potential to start from bio-derived alcohols, this concept avoids the direct use of the reactive aldehyde intermediates, enables addition of high substrate concentrations in one liquid phase while maintaining enzyme activity and enables a simplified product isolation with diminished waste formation. [ABSTRACT FROM AUTHOR]

A table of contents for the Green Chemistry topics include thermochemical conversion for second-generation in biofuel production, carbon dioxide as catalyst in bio-jet fuel production, and methyl aromatics activation via photocatalysis and is presented.

Photosynthesis may be described as light-driven oxidation of water and subsequent use of the generated reducing equivalents to fix CO2 and synthesize higher energy organic compounds, such as carbohydrates. The transposition of the sustainable and atom-efficient strategy of water oxidation to in vitro controlled biocatalytic reactions is poorly studied but is of high interest for the development of photobiocatalysis, and eco-friendly catalytic tools in a wider sense. Here we demonstrate that light-driven oxidation of water catalysed by vanadium-doped TiO2 (V-TiO2), a re-usable photocatalyst, can provide the electrons that lytic polysaccharide monooxygenases (LPMOs) need to oxidatively deconstruct biomass polysaccharides. The demonstration that electrons may be generated by water oxidation alleviates the need for an externally added electron donor, which so far has been a prerequisite for LPMO activity. Importantly, photocatalytic LPMO activation was achieved in the absence of redox mediators, which represents the first demonstration of mediator-free electron transfer from V-TiO2 particles to a redox enzyme, expanding the repertoire of known and conceivable photobiocatalytic reactions. Fundamentally, this photobiocatalytic system allows activation and tight control of LPMO activity, thus offering new tools for mechanistic studies of these industrially important and ubiquitous enzymes. The latter is illustrated by real-time studies of the redox state of an LPMO, using the controllable light-V-TiO2 technology for LPMO reduction and a novel fluorescence method for monitoring re-oxidation. We also show that the light-V-TiO2 technology may be used to study pre-activation of LPMOs. [ABSTRACT FROM AUTHOR]