Diethylaminodifluorosulfinium tetrafluoroborate (XtalFluor-E) and morpholinodifluorosulfinium tetrafluoroborate (XtalFluor-M) are crystalline fluorinating agents that are more easily handled and significantly more stable than Deoxo-Fluor, DAST, and their analogues. These reagents can be prepared in a safer and more cost-efficient manner by avoiding the laborious and hazardous distillation of dialkylaminosulfur trifluorides. Unlike DAST, Deoxo-Fluor, and Fluolead, XtalFluor reagents do not generate highly corrosive free-HF and therefore can be used in standard borosilicate vessels. When used in conjunction with promoters such as Et3N·3HF, Et3N·2HF, or DBU, XtalFluor reagents effectively convert alcohols to alkyl fluorides and carbonyls to gem-difluorides. These reagents are typically more selective than DAST and Deoxo-Fluor and exhibit superior performance by providing significantly less elimination side products.

3D printing is a rapidly growing technology that has an enormous potential to impact a wide range of industries such as engineering, art, education, medicine, and aerospace. The flexibility in design provided by this technique offers many opportunities for manufacturing sophisticated 3D devices. The most widely utilized method is an extrusion‐based solid‐freeform fabrication approach, which is an extremely attractive additive manufacturing technology in both academic and industrial research communities. This method is versatile, with the ability to print a range of dimensions, multimaterial, and multifunctional 3D structures. It is also a very affordable technique in prototyping. However, the lack of variety in printable polymers with advanced material properties becomes the main bottleneck in further development of this technology. Herein, a comprehensive review is provided, focusing on material design strategies to achieve or enhance the 3D printability of a range of polymers including thermoplastics, thermosets, hydrogels, and other polymers by extrusion techniques. Moreover, diverse advanced properties exhibited by such printed polymers, such as mechanical strength, conductance, self‐healing, as well as other integrated properties are highlighted. Lastly, the stimuli responsiveness of the 3D printed polymeric materials including shape morphing, degradability, and color changing is also discussed.

Enzymes, as nature’s catalysts, speed up the very reactions that make life possible. Hydrolytic enzymes are a particularly important enzyme class responsible for the catalytic breakdown of lipids, starches, and proteins in nature, and they are displaying increasing industrial relevance. While the unrivalled catalytic effect of enzymes continues to be unmatched by synthetic systems, recent progress has been made in the design of hydrolase-inspired catalysts by imitating and incorporating specific features observed in native enzyme protein structures. The development of such enzyme-inspired materials holds promise for more robust and industrially relevant alternatives to enzymatic catalysis, as well as deeper insights into the function of native enzymes. This Review will explore recent research in the development of synthetic catalysts based on the chemistry of hydrolytic enzymes. A focus on the key aspects of hydrolytic enzyme structure and catalytic mechanism will be exploredincluding active-site chemistry, tuning transition-state interactions, and establishing reactive nanoenvironments conducive to attracting, binding, and releasing target molecules. A key focus is to highlight the progress toward an effective, versatile hydrolase-inspired catalyst by incorporating the molecular design principles laid down by nature.

The efficient conversion of formate into oxalate could enable the industrial‐scale synthesis of multi‐carbon compounds from CO2 by C−C bond formation. We found conditions for the highly selective catalytic conversion of molten alkali formates into pure solid oxalate salts. Nearly quantitative conversion was accomplished by calcination of sodium formates with sodium hydride. A catalytic mechanism proceeding through a carbonite intermediate, generated upon H2 evolution, was supported by density functional theory calculations, Raman spectroscopy, and the observed changes in the catalytic performance upon changing the nature of the base or the reaction conditions. Whereas the conversion of formate into oxalate by using a hydroxide ion catalyst was previously studied, hydride ion catalysis and the chain reaction mechanism for the conversion involving a carbonite ion intermediate are reported herein for the first time.

The title salts are more stable and more easily handled than DAST and Deoxo-Fluor and can be prepared in a safer and more cost-effective manner. In combination with DBU, NEt3·3HF, or NEt3·2HF they allow convenient formation of alkyl fluorides from alcohols, gem-difluorides from carbonyl compounds, and α-fluorothioethers from sulfoxides. -(L'HEUREUX, A.; BEAULIEU, F.; BENNETT, C.; BILL, D. R.; CLAYTON, S.; LAFLAMME, F.; MIRMEHRABI, M.; TADAYON, S.; TOVELL, D.; COUTURIER*, M.; J. Org.

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Well-defined steroid hormone dimers and organogels were produced via af acile and scalables ynthesis using oxime click chemistry.T he versatile synthetic procedure extends to aw ide range of hormones and linker groups exemplified here through the synthesis of cortisoland progesterone-dimers linked via hydrophobic, hydrophilic or functional groups. This method was also extended to the synthesis of cortisone-based organogels. Owing to the dynamic nature of the oxime bond, the hormonebased materials are degradable via acidic hydrolysis and transoximination representing new materials for the controlled releaseo fs teroid hormones.

Polyethylene (PE) is the most used commodity polymer today. The reason PE has found widespread use in a range applications is due to the unique and tuneable properties available by tuning the molecular weight, the degree of branching, and choice of comonomers made by Ziegler-Natta or metallocene chemistry.1 The common industrial techniques used to make PEs have limited versatility to prepare functional PEs with, especially with polar comonomers. However, the range of applications could be increased further with the ability to prepare functional polyolefins.A range of techniques have been developed to prepare functional PE polymers. 3 The Wagner group has developed a number of strategies using acyclic diene metathesis (ADMET) polymerizations. [4][5][6][7][8] Recently, Hillmyer and coworkers 9 developed a two-step synthesis using ring-opening metathesis polymerization (ROMP) of acetoxy functional cyclooctene to produce stereo regular functional polyolefins. A range of functional groups have been incorporated into PE's structure including: phosphonic ester and phosphonic acid, 10 carboxylic acid, 11 amino, 12 alcholol, 13 methylimidazolium bromide. 6Most of the strategies developed require functionalization of monomers. Herein, we describe a versatile platform synthesis whereby the one polymer platform can be functionalized with a number of polar or nonpolar groups.Here, we have taken inspiration from work that has utilized norbornene 14 and internal double bonds produced from ROMP polymers [15][16][17] and poly(butadienes) 18 as functional handles using thiol-ene chemistry; this is a new strategy in the development of a range of functional polyolefins. Our simple and versatile approach to develop functional polyethylenes is based on the preparation of polycyclooctene (P oct ) by ROMP of cyclooctene with Grubbs second generation catalyst. Subsequent functionalization reactions of the internal alkene bond can be achieved with a range of thiol functional molecules, via photoactivated thiol-ene click chemistry to prepare a range of functional PEs,19,20 providing a unique and versatile technique to functionalize PEs.ROMP polymerizations of cyclooctene were performed for 1 h in dichloromethane at 30 C, resulting in a library of polymers with M n ranging from 7 to 165 kDa and typical dispersity index of about 1.6, see Supporting Information Table S1 for details. These versatile platform polymers were used to demonstrate facile functionalization strategies using thiol-ene photochemistry, with a wide range of thiols (Scheme 1). The thiol-ene photoinitiated reactions were performed in appropriate solvents with an excess amount of thiol-containing small molecules (2-5 equivalents per double bond). 2,2-Dimethoxy-2-phenylacetophenone (DMPA) was used as a photoinitiator and irradiated with UV (365 nm) light for 6 h.