Saikat Dutta

Imparting Functionality to Biocatalysts via Embedding Enzymes into Nanoporous Materials by a de Novo Approach: Size-Selective Sheltering of Catalase in Metal–Organic Framework Microcrystals

We develop a new concept to impart new functions to biocatalysts by combining enzymes and metal-organic frameworks (MOFs). The proof-of-concept design is demonstrated by embedding catalase molecules into uniformly sized ZIF-90 crystals via a de novo approach. We have carried out electron microscopy, X-ray diffraction, nitrogen sorption, electrophoresis, thermogravimetric analysis, and confocal microscopy to confirm that the ~10 nm catalase molecules are embedded in 2 μm single-crystalline ZIF-90 crystals with ~5 wt % loading. Because catalase is immobilized and sheltered by the ZIF-90 crystals, the composites show activity in hydrogen peroxide degradation even in the presence of protease proteinase K.

Hydrodeoxygenation of the Angelica Lactone Dimer, a Cellulose-Based Feedstock: Simple, High-Yield Synthesis of Branched C7–C10 Gasoline-like Hydrocarbons†

Dehydration of biomass-derived levulinic acid under solid acid catalysis and treatment of the resulting angelica lactone with catalytic K2 CO3 produces the angelica lactone dimer in excellent yield. This dimer serves as a novel feedstock for hydrodeoxygenation, which proceeds under relatively mild conditions with a combination of oxophilic metal and noble metal catalysts to yield branched C7 -C10 hydrocarbons in the gasoline volatility range. Considering that levulinic acid is available in >80u2009% conversion from raw biomass, a field-to-tank yield of drop-in, cellulosic gasoline of >60u2009% is possible.

Synthesis of the natural herbicide δ-aminolevulinic acid from cellulose-derived 5-(chloromethyl)furfural

Cellulose-derived 5-(chloromethyl)furfural is converted into δ-aminolevulinic acid in three chemical steps involving conversion to 5-(azidomethyl)furfural, photooxidation, and catalytic hydrogenation in 68% overall yield. δ-Aminolevulinic acid is a natural product with important agrochemical and pharmaceutical applications.

Efficient, metal-free production of succinic acid by oxidation of biomass-derived levulinic acid with hydrogen peroxide

A practical, scalable, metal-free synthesis of succinic acid from the biomass-derived platform chemical levulinic acid is described. Treatment of levulinic acid with the inexpensive, simple oxidant hydrogen peroxide under the catalytic action of trifluoroacetic acid gives succinic acid in high yield and enables facile product isolation by simple distillation of the volatile catalyst and byproducts.

Synthesis of ranitidine (Zantac) from cellulose-derived 5-(chloromethyl)furfural

The biomass-derived platform chemical 5-(chloromethyl)furfural is converted into the blockbuster antiulcer drug ranitidine (Zantac) in four steps with an overall 68% isolated yield.

Novel pathways to 2,5-dimethylfuran via biomass-derived 5-(chloromethyl)furfural

2,5-Dimethylfuran (DMF) is one of the most actively pursued biomass-derived chemicals due to the fact that it can serve both as a biofuel and an intermediate for drop-in terephthalate polymers. DMF can be accessed via catalytic hydrogenation of 5-(hydroxymethyl)furfural (HMF), but the difficult accessibility of HMF from cellulosic biomass is a major impediment to the commercial development of such a process. Alternatively, 5-(chloromethyl)furfural (CMF) is freely accessible in high yield directly from raw biomass and is shown here to be efficiently reduced to DMF under mild conditions via simple derivatives (aldimine, acetal).

Synthesis of the Insecticide Prothrin and Its Analogues from Biomass-Derived 5‑(Chloromethyl)furfural

Prothrin, a synthetic pyrethroid insecticide, was synthesized from the biomass-derived platform chemical 5-(chloromethyl)furfural in six steps and overall 65% yield. Two structural analogues of prothrin were also prepared following the same synthetic approach. Preliminary testing of these furan-based pyrethroids against the yellow fever mosquito Aedes aegypti indicates promising insecticidal activities.

Resorcinol-templated synthesis of a cofacial terpyridine in crystalline π-stacked columns.

A resorcinol achieves a templated stereospecific and near-quantitative synthesis of a cofacial terpyridine in the solid state. The solid-state synthesis occurs in one-dimensional π-stacked columns with reactivities highly sensitive to peripheral groups attached to the template.

ZIF-8 Derived, Nitrogen-Doped Porous Electrodes of Carbon Polyhedron Particles for High-Performance Electrosorption of Salt Ions

Three-dimensional (3-D) ZIF-8 derived carbon polyhedrons with high nitrogen (N) content, (denoted as NC-800) are synthesized for their application as high-performance electrodes in electrosorption of salt ions. The results showed a high specific capacitance of 160.8u2009F·g−1 in 1 M NaCl at a scan rate of 5u2009mV·s−1. Notably, integration of 3-D mesopores and micropores in NC-800 achieves an excellent capacitive deionization (CDI) performance. The electrosorption of salt ions at the electrical double layer is enhanced by N-doping at the edges of a hexagonal lattice of NC-800. As evidenced, when the initial NaCl solution concentration is 1u2009mM, the resultant NC-800 exhibits a remarkable CDI potential with a promising salt electrosorption capacity of 8.52u2009mg·g−1.

Production of 5-(chloromethyl)furan-2-carbonyl chloride and furan-2,5-dicarbonyl chloride from biomass-derived 5-(chloromethyl)furfural (CMF)

Acid chloride derivatives of 5-(chloromethyl)furan-2-carboxylic acid and furan-2,5-dicarboxylic acid (FDCA) can be produced in high yield by treatment of the precursor aldehydes 5-(chloromethyl) furfural (CMF) and 2,5-diformylfuran (DFF) with tert-butyl hypochlorite, which is inexpensively prepared from commercial bleach and tert-butanol. 5-(Chloromethyl)furan-2-carbonyl chloride (CMFCC) and furan-2,5-dicarbonyl chloride (FDCC) are highly useful intermediates for the production of furoate ester biofuels and polymers of FDCA.