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A facile and efficient method for the synthesis of primary phosphinamides from Ar 2 P(O)-H reagents with stable and readily available ammonium carbonate as an ammonia source is disclosed herein for the first time. This ethyl bromoacetate-mediated primary amination proceeds smoothly under mild and simple conditions, without any metal catalyst or oxidant. Moreover, this method is also appropriate for the reaction of Ar 2 P(O)-H with a variety of amines, alcohols, and phenols to construct P-N or P-O bonds, with features of handy operation, good functional group tolerance, and broad substrate scope.

The human genome contains at least 35 genes that encode Golgi sulfotransferases that function in the secretory pathway, where they are involved in decorating glycosaminoglycans, glycolipids, and glycoproteins with sulfate groups. Although a number of important interactions by proteins such as selectins, galectins, and sialic acid-binding immunoglobulin-like lectins are thought to mainly rely on sulfated O-glycans, our insight into the sulfotransferases that modify these glycoproteins, and in particular GalNAc-type O-glycoproteins, is limited. Moreover, sulfated mucins appear to accumulate in respiratory diseases, arthritis, and cancer. To explore further the genetic and biosynthetic regulation of sulfated O-glycans, here we expanded a cell-based glycan array in the human embryonic kidney 293 (HEK293) cell line with sulfation capacities. We stably engineered O-glycan sulfation capacities in HEK293 cells by site-directed knockin of sulfotransferase genes in combination with knockout of genes to eliminate endogenous O-glycan branching (core2 synthase gene GCNT1) and/or sialylation capacities in order to provide simplified substrates (core1 Galβ1-3GalNAcα1-O-Ser/Thr) for the introduced sulfotransferases. Expression of the galactose 3-O-sulfotransferase 2 in HEK293 cells resulted in sulfation of core1 and core2 O-glycans, whereas expression of galactose 3-O-sulfotransferase 4 resulted in sulfation of core1 only. We used the engineered cell library to dissect the binding specificity of galectin-4 and confirmed binding to the 3-O-sulfo-core1 O-glycan. This is a first step toward expanding the emerging cell-based glycan arrays with the important sulfation modification for display and production of glycoconjugates with sulfated O-glycans., Competing Interests: Conflict of interest University of Copenhagen has filed a patent application on the cell-based display platform. GlycoDisplay ApS, Copenhagen, Denmark, has obtained a license to the field of the patent application. Y. N. and H. C. are cofounders of GlycoDisplay ApS and hold ownerships in the company. H. L. is cofounder and consultant with Galecto, Inc. All other authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Photocatalytic oxidative benzylic bromination with hydrobromic acid (HBr) and hydrogen peroxide (H 2 O 2 ) is a green process for the synthesis of benzyl bromides, but suffers from the risk of explosion when performing it in a batch reactor. This disadvantage could be overcome by running the reaction in a microchannel reactor. In this work, a green and safe process for the synthesis of 2,6-dichlorobenzyl bromide (DCBB) was developed by conducting selective benzylic bromination of 2,6-dichlorotoluene (DCT) with H 2 O 2 as an oxidant and HBr as a bromine source in a microchannel reactor under light irradiation. The reaction parameters were optimized, and the conversion of DCT reached up to 98.1% with a DCBB yield of 91.4% under the optimal reaction conditions., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Disclosed herein is a cross-dehydrogenative-coupling reaction of N -heterocycles including 1,2,4-triazine-3,5(2 H , 4 H )-diones and quinoxaline-2(1 H )-ones with N -methylanilines to form C(sp 2 )-C(sp 3 ) under visible-light illumination and ambient air at room temperature. In this process, easily available Ru(bpy) 3 Cl 2 ·6H 2 O serves as the catalyst, and air acts as the green oxidant. This method features high atom economy, environmental friendliness, and convenient operation and provides an efficient and practical access to aminomethyl-substituted N -heterocycles with extensive functional group compatibility in 40-86% yields.

Photocatalysis with potentially low cost and sustainable utilization is a typically environmentally benign method for the degradation of organic pollutants, but the rational design and fabrication of photocatalysts with high catalytic performance is still an enormous challenge. The efficient segregation of photogenerated electron-hole pairs in photocatalysts is a key and essential factor to decide photocatalytic activity. Herein, a novel Step-scheme (S-scheme) heterojunction photocatalyst, a g-C3N4/Bi2MoO6 (g-CN/BMO) composite, was successfully fabricated using g-C3N4 nanosheet-wrapped Bi2MoO6 microspheres. By adjusting the amount of g-C3N4 in BMO, a series of g-CN/BMO composites was prepared while optimizing posttreatment temperature. The resulting g-CN/BMO indicated well the photocatalytic performance for the degradation of phenol and hydrogen evolution reactions, especially, 100 g of g-CN was integrated into 100 g of the pre-calcined BMO at 200 °C to produce 100% g-CN/BMO-200, showing the highest photocatalytic performance compared to single composite BMO, BMO-200, g-CN, and g-CN/BMO-200 with other mass ratios. Combining the results from the density functional theory calculations and the results of X-ray photoelectron spectroscopy, for S-scheme heterojunction-structured g-CN/BMO-200, the internal electric field-, band edge bending- and coulomb interaction-driven efficient segregation of photogenerated electrons and holes at the interface is elucidated to explain the photocatalytic mechanism, and the resulting holes on the VB of BMO and electrons on the CB of g-CN are responsible for the improvement of the photocatalytic performance. This study revealed that for the S-scheme g-CN/BMO composite the internal electric field, band edge bending and coulomb interaction at the interface between g-CN and BMO can not only promote the effective segregation of electrons and holes, but also retain stronger redox ability. Such an investigation provides a facile and simple strategy to fabricate novel S-scheme heterojunction-structured photocatalysts for solar energy conversion.

The modification of quinoxalin-2(1 H )-ones via direct C-H bond functionalization has begun to receive widespread attention, due to quinoxalin-2(1 H )-one derivatives' various biological activities and pharmaceutical properties. This mini review concentrates on the accomplishments of arylation, trifluoromethylation, alkylation, and alkoxylation of quinoxalin-2(1 H )-ones with hypervalent iodine(III) reagents as reaction partners or oxidants. The reaction conditions and mechanisms are compared and discussed in detail., (Copyright © 2020 Tan, Wang, Zhang, Zhang and Zhao.)

A facile and effective alkoxylation protocol of quinoxalin-2(1 H )-ones with primary or secondary alcohols via cross-dehydrogenative coupling under catalyst-free conditions has been disclosed. This method provides a powerful and convenient access to 3-alkoxylquinoxalin-2(1 H )-ones in good to excellent yields by utilizing PhI(OTFA) 2 as an oxidant and allows to easily obtain potential drug molecules containing 3-alkoxylquinoxalin-2(1 H )-one skeletons.

To discern the distinctive effect of the C[double bond, length as m-dash]C bond and the phenyl bridge on the photophysical and chemical properties of D-π-A molecular systems, three new dicyanovinyl substituted push-pull chromophores 1-3 containing either a C[double bond, length as m-dash]C bond or a phenyl ring as the central π-linker were synthesized by the Suzuki-Miyaura and Knoevenagel reactions. Together with the counterpart of 1 developed by Zhang's group (TPE-z), their optical properties and single crystal structures were systematically and comparatively investigated. Notably, the simple π-extension of a C[double bond, length as m-dash]C linker to a phenyl ring between electron donor and electron acceptor moieties could greatly affect the photophysical properties of chromophores, particularly leading to significant hypsochromic shifts in both absorption and emission spectra. Meanwhile, as a node of twisted sections in chromophores, the C[double bond, length as m-dash]C bond was demonstrated to play an important role in the nonradiative relaxation of excited states, as compared to the rigid phenyl spacer. Moreover, the three chromophores were found to display spectral responses to hydrazine with slightly different sensitivities, and visual detection of hydrazine in the gaseous state was achieved via using readily fabricated paper test strips.