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A highly tunable defluorophosphorylation of fluorinated peroxides for the preparation of C3,4-diphosphoryl furans and C4-monophosphoryl furans under conditions with no added transition metals is disclosed.

Simple and commercially available magnesium halides catalyzed the hydroboration of various isocyanates and ketones.

An unprecedented four-component defluorinative reaction of allylic fluorides, amidines, and Cs2CO3 for the convenient synthesis of valuable pyrimidine-containing amidino carbamates under transition-metal-free conditions was developed.

A green and sustainable electrochemical hydroboration of carbonyl compounds with HBpin has been reported for the first time. Under catalyst-free and additive-free mild reaction conditions the corresponding boronic esters were obtained in excellent yields

A copper-catalysed three-component reaction utilizing readily available feedstocks was investigated, providing an operationally simple and practical route to trifluoromethyl allenes under mild and environmentally friendly conditions.

A practical and convenient approach that enabled radical-mediated conjugate addition of unreactive alkenes to electron-deficient alkenes leading to a broad range of substituted malononitriles was disclosed.

An efficient defluorinative net-[3 + 3]-cyclization strategy for the construction of perfluoroalkyl-substituted pyrimidine derivatives by using a series of perfluoroalkyl alkynes and amidines as starting materials was developed. The present reaction proceeded successfully under transition-metal-free conditions to form two new C–N bonds and a new heterocyclic ring through a sequence of hydroamination, defluorination, and annulation. The desired pyrimidines could be obtained with good functional group tolerance and moderate to good yields. Moreover, the distinctive fluorine effects of perfluoroalkyl substituents are vital for tuning the reactivity of alkynes for the anticipated defluorinative annulation. The pendant π system would lower associated bond dissociation energy significantly compared to that of a nonactivated C(sp3)–F bond.

An efficient transition-metal-free hydrodefluorination reaction of trifluoromethyl alkenes for accessing gem-difluoroalkenes is developed. It was surprising to find that the phosphoryl anion is able to mediate the defluorination.

It is attractive to establish an efficient and practical platform affording functional compounds using readily available feedstocks as starting materials under mild conditions. We describe a direct copper-catalyzed fluorocarboalkynylation of the readily available alkynes with excellent regio- and stereoselectivity. A wide range of conjugated trifluoromethyl 1,3-enynes were obtained in good yields by this operationally simple strategy. The mechanistic experiments and DFT calculation revealed that a radical-mediated process was involved in the catalytic cycle.

We have developed a modular, convenient and practical copper-catalyzed platform for the preparation of alkene nitriles from corresponding cycloketoxime esters via radical-mediated C–C bond cleavage. A broad scope of cycloketoxime esters (4-membered to 8-membered) and some complex substrates derived from natural product derivatives performed well, affording corresponding ring opening products in the presence of copper salts. Moreover, the etherification, oxidation and alkynylation of cycloketoxime esters could also be achieved under variable copper-catalyzed conditions.

Bacterial cellulose (BC), sustainable biomass, has long been envisioned as a fantastic biomass material since it was discovered by Brown in 1886. BC cultivated in static medium appears as a never-dried hydrogel, wherein numerous nanofibers are highly interconnected, building into a three-dimensional (3D) architecture. Although BC has achieved great success in the area of biological medicine, the electronic inertness and susceptible bio-invasion restrict its further applications demanding electronic migration and durability. Carbonization has been employed to endow BC with superior conductivity and chemical tolerance without destroying the 3D architecture. Moreover, carbonized BC (CBC) exhibits exceptional properties such as ultralightweight, high surface area, good volumetric resilience, and superhydrophobicity, which are necessary for electrochemical energy, microwave attenuation, and selective absorption. The industrial production of BC facilitates the massive fabrication of high value-added CBC with low-cost precursors. This review summarizes the latest developments on the CBC-based functional materials, including state-of-the-art design concepts and synthetic strategies. Our prospects on the major obstacles in the approach of further exploitation of CBC, as well as the promising avenues in front of these issues are proposed in this review.

A series of asymmetrical β-diketiminate ligand stabilized magnesium(I) complexes have been successfully synthesized and structurally characterized via single crystal X-ray diffraction. When they were employed as efficient catalysts in the hydroboration of aryl, alkyl and alicyl epoxides with pinacolborane (HBpin), the resultant borate ester products were obtained with high yields and high regioselectivities. The results also revealed that they showed a marked preference for the branched Markovnikov hydroborated products instead of the linear anti-Markovnikov borate esters which are typically formed in protocols involving transition metal catalysts. The preliminary hydroboration reaction mechanism has been investigated via the corresponding DFT calculation.

Correction for ‘Copper-catalysed synthesis of trifluoromethyl allenes via fluoro-carboalkynylation of alkenes’ by Mengning Wang et al., Org. Chem. Front., 2022, 9, 1844–1849, https://doi.org/10.1039/D1QO01823J.

The hydroboration of a wide range of ketones with pinacolborane can be achieved under catalyst-free and solvent-free conditions to provide the corresponding boronic esters in quantitative yields. A large gram-scale hydroboration of acetophenone with HBpin under the same conditions was also performed to afford the alcohol product in a high yield thus demonstrating the scalability of the newly developed simple protocol.

In this paper, we develop quercetin-coated Fe3O4 nanoparticles (QMNPS) as a sensor for the detection and removal of Pb2+ and Cu2+ based on low-field NMR. QMNPS were characterized by TEM, FTIR and XRD. The NMR sensor showed high selectivity toward Pb2+ or Cu2+. The standard curves for ΔT2-ion concentration showed good correlations, i.e., R2 = 0.9912 for Pb2+ and 0.9983 for Cu2+; the linear ranges and the limits of detection were 4.8 × 10−6–1 × 10−4 mol L−1 and 1.6 × 10−6 mol L−1 for Pb2+, and 5.0 × 10−6–1 × 10−4 mol L−1 and 2.0 × 10−6 mol L−1 for Cu2+, respectively. The calculated maximum adsorption capacity was about 71 mg for Cu2+ and 68 mg for Pb2+ per gram of QMMP, which was superior to the results of some previous reports. The detection and removal of Pb2+ or Cu2+ was based on the coordination reaction between the NMR sensor of QMNPs and Pb2+ or Cu2+, which led to the aggregation of QMNPs. As a result, the proposed NMR sensor was successfully applied for the determination and removal of Pb2+ and Cu2+ in contaminated water and urine samples with excellent recoveries and high adsorbent capacities.

A series of bulky secondary amines were treated with two equiv. Grignard reagent MeMgI at low temperature to yield the corresponding magnesium methyl complexes (1–4) in high yields. The prepared complexes have been comprehensively characterized. All four complexes exhibited very high reactivity as efficient pre-catalysts in the catalytic hydroboration of ketones with pinacolborane under mild conditions and at low catalyst loadings.

A porous cobalt-based metal–organic framework [CoL2−]n (L = 5-(pyrimidin-5-yl) isophthalic acid) (termed NJFU-2), has been designed by self-assembling [Co2(COO)4] paddlewheel SBUs and a novel trigonal hetero-functional ligand. Moreover, the activated sample NJFU-2a exhibits a moderate BET surface area of 1223 m2 g−1, large CO2 uptake (6.14 wt% at 0.15 bar and 298 K) and high selectivity for CO2 over CH4 and N2 at room temperature, estimated by the Ideal Adsorbed Solution Theory (IAST).

Reactions of [Pt(PCy(3))(2)] (Cy = cyclohexyl) with group 12 metal dihalides have afforded the novel metal only Lewis pair (MOLP) complexes, [(Cy(3)P)(2)Pt→MX(2)] (M = Zn or Cd, X = Br or I), or the oxidative addition product, trans-[(Cy(3)P)(2)(I)PtHgI]. The zinc complex represents the first MOLP to contain an unsupported Pt→Zn linkage.

The asymmetric cycloaddition reactions of 3,4-dimethyl-1-phenylarsole and (Z/E)-diphenyl-1-propenylphosphine/diphenyl-1-styrylphosphine promoted by a chiral organopalladium(ii) complex derived from (S)-[1-(dimethylamino)ethyl]naphthalene proceeded stereoselectively to generate different exo/endo-products. The reactions involving the (Z/E)-methyl substituted phosphines gave the individual optically pure exo- and endo-cycloadducts in very high stereoselectivity (33 : 1). However, when the methyl group was replaced by a Ph moiety both (Z/E)-phenyl substituted phosphines produced the same endo-cycloadduct in a stereoselectivity of 15 : 1. Every reaction produced five new chiral centers (four of them are sterically independent) in a single step and all three optically pure As-P heterobidentate ligands were obtained in high yields. The mechanism involved in the conversion of exo- to endo-product was investigated via density functional theory calculations. Computational results were consistent with the experimentally observed endo/exo-selectivity.