Based on the principles and metrics of green chemistry and sustainable development, biocatalysis is both a green and sustainable technology. This is largely a result of the spectacular advances in molecular biology and biotechnology achieved in the past two decades. Protein engineering has enabled the optimization of existing enzymes and the invention of entirely new biocatalytic reactions that were previously unknown in Nature. It is now eminently feasible to develop enzymatic transformations to fit predefined parameters, resulting in processes that are truly sustainable by design. This approach has successfully been applied, for example, in the industrial synthesis of active pharmaceutical ingredients. In addition to the use of protein engineering, other aspects of biocatalysis engineering, such as substrate, medium, and reactor engineering, can be utilized to improve the efficiency and cost-effectiveness and, hence, the sustainability of biocatalytic reactions. Furthermore, immobilization of an enzyme ...

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Role of Biocatalysis in Sustainable Chemistry

Coumarins are a very large family of compounds containing the unique 2H-chromen-2-one motif, as it is known according to IUPAC nomenclature. Coumarin derivatives are widely found in nature, especially in plants and are constituents of several essential oils. Up to now, thousands of coumarin derivatives have been isolated from nature or produced by chemists. More recently, the coumarin platform has been widely adopted in the design of small-molecule fluorescent chemosensors because of its excellent biocompatibility, strong and stable fluorescence emission, and good structural flexibility. This scaffold has found wide applications in the development of fluorescent chemosensors in the fields of molecular recognition, molecular imaging, bioorganic chemistry, analytical chemistry, materials chemistry, as well as in the biology and medical science communities. This review focuses on the important progress of coumarin-based small-molecule fluorescent chemosensors during the period of 2012-2018. This comprehensive and critical review may facilitate the development of more powerful fluorescent chemosensors for broad and exciting applications in the future.

Coumarin-Based Small-Molecule Fluorescent Chemosensors.

Heterogeneous catalysis is a promising technology for the valorization of renewable biomass to sustainable advanced fuels and fine chemicals. Porosity and nanostructure are the most versatile features of heterogeneous solid catalysts, which can greatly determine the accessibility of specific active sites, reaction mechanisms, and the selectivity of desirable products. Hence, the precise tuning of porosity and nanostructure has been a potential strategy towards developing novel solid catalysts with indispensable characteristics for efficient biomass valorization. Herein, we present a timely and comprehensive review of the recent advances in catalytic biomass conversions over microporous zeolites, mesoporous silicas, and nanostructured metals/metal oxides. This review covers the catalytic processing of both edible (lipids and starch) and non-edible (lignocellulose) biomass as well as their derived compounds, along with a systematic evaluation of catalyst reusability/kinetic/mechanistic aspects in the relevant processes. The key parameters essential for tailoring particle size, morphology, porosity, acid–base, and redox properties of solid catalysts are emphasized, while discussing the ensuing catalytic effects towards the selective conversion of biomass into desirable chemicals. Special attention has been drawn to understand the role of water in liquid phase biomass conversions as well as the hydrothermal stability and the deactivation of nanoporous catalysts. We believe this comprehensive review will provide new insights towards developing state-of-the-art solid catalysts with well-defined porosity and nanoscale properties for viable biomass conversion.

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Advances in porous and nanoscale catalysts for viable biomass conversion.

Colorimetric metal ion sensors – A comprehensive review of the years 2011–2016

Nanocrystalline Sn-Beta zeolites have been successfully prepared via an improved two-step postsynthesis strategy, which consists of creating vacant T sites with associated silanol groups by dealumination of parent H-Beta and subsequent dry impregnation of the resulting Si-Beta with organometallic dimethyltin dichloride. Characterization results from UV−vis, XPS, Raman, and 119 Sn solid-state MAS NMR reveal that most Sn species have been successfully incorpo- rated into the framework of Beta zeolite through the postsynthesis process and exist as isolated tetrahedral Sn(IV) in open arrangement. The creation of strong Lewis acid sites upon Sn incorporation is confirmed by FTIR spectroscopy with pyridine adsorption. The Sn-Beta Lewis acid catalysts are applied in the ring-opening hydration of epoxides to the corresponding 1,2-diols under near ambient and solvent-free conditions, and remarkable activity can be obtained. The impacts of Lewis acidity, preparation parameters, and reaction conditions on the catalytic performance of Sn-Beta zeolites are discussed in detail.

Improved Postsynthesis Strategy to Sn-Beta Zeolites as Lewis Acid Catalysts for the Ring-Opening Hydration of Epoxides

The three-dimensional sponge-like mesoporous material TUD-1 is straightforward to prepare. Its synthesis can readily be modified to introduce metals into the framework of TUD-1, imparting many different catalytic activities. M-TUD-1 catalysts have proven to be very active, unlimited by diffusion and very stable. By combining two metals into one TUD-1 catalyst, synergy between Lewis and Bronsted acid sites could be induced; incorporation of zeolites similarly gave rise to synergy. In addition to successful applications in redox-, acid- and photo-catalysis TUD-1 proved to be an excellent carrier material for catalysts, enabling new applications. TUD-1 was used as a contrast agent and drug delivery system, indicating that this material is but at the beginning of its potential applications.

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TUD-1: synthesis and application of a versatile catalyst, carrier, material ...,

SnTUD-1: a solid acid catalyst for three component coupling reactions at room temperature

Niobium incorporated mesoporous silicate, Nb-KIT-6: Synthesis and characterization

Fenton-like degradation of Bisphenol A catalyzed by mesoporous Cu/TUD-1

A zirconium-incorporated Ia3d cubic three-dimensional (3-D) mesoporous silicate, KIT-6, with different zirconium loadings, was synthesized via a one-step direct hydrothermal synthesis procedure emp...

Anand Ramanathan

Papers

TUD-1: synthesis and application of a versatile catalyst, carrier, material ...,

SnTUD-1: a solid acid catalyst for three component coupling reactions at room temperature

Niobium incorporated mesoporous silicate, Nb-KIT-6: Synthesis and characterization

Fenton-like degradation of Bisphenol A catalyzed by mesoporous Cu/TUD-1

Synthesis and Dehydration Activity of Novel Lewis Acidic Ordered Mesoporous Silicate: Zr-KIT-6