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Abstract The migratory insertion of metal-hydride into alkene has allowed regioselective access to organometallics, readily participating in subsequent functionalization as one conventional pathway of hydroalkylation, whereas analogous process with feedstock alkyne is drastically less explored. Among few examples, the regioselectivity of metal-hydride insertion is mostly governed by electronic bias of alkynes. To alter the regioselectivity and drastically expand the intermediate pools that we can access, one aspirational design is through alternative nickel-alkyl insertion, providing opposite regioselectivity induced by steric demand. Leveraging in situ formed nickel-alkyl species, we herein report the regio- and enantioselective hydroalkylation of alkynes with broad functional group tolerance, excellent regio- and enantioselectivity, enabling efficient route to diverse valuable chiral allylic amines motifs. Preliminary mechanistic studies indicate the aminoalkyl radical species can participate in metal-capture and lead to formation of nickel-alkyl, of which the migratory insertion is key to reverse regioselectivity observed in metal-hydride insertion.

Abstract Polymerization-driven removal of pollutants in advanced oxidation processes (AOPs) offers a sustainable way for the simultaneous achievement of contamination abatement and resource recovery, supporting a low-carbon water purification approach. However, regulating such a process remains a great challenge due to the insufficient microscopic understanding of electronic structure-dependent reaction mechanisms. Herein, this work probes the origin of catalytic pollutant polymerization using a series of transition metal (Cu, Ni, Co, and Fe) single-atom catalysts and identifies the d-band center of active site as the key driver for polymerization transfer of pollutants. The high-valent metal-oxo species, produced via peroxymonosulfate activation, are found to trigger the pollutant removal via polymerization transfer. Phenoxyl radicals, identified by the innovative spin-trapping and quenching approaches, act as the key intermediate in the polymerization reactions. More importantly, the oxidation capacity of high-valent metal-oxo species can be facilely tuned by regulating their binding strength for peroxymonosulfate through d-band center modulation. A 100% polymerization transfer ratio is achieved by lowering the d-band center. This work presents a paradigm to dynamically modulate the electronic structure of high-valent metal-oxo species and optimize pollutant removal from wastewater via polymerization.

The efficient construction of trifluoromethylated alkanes bearing a CF3 chiral center is of great importance in organic synthesis. Here, the authors disclose the enantioselective syntheses of α-trifluoromethylated allylic alkanes via reductive trifluoroalkylation.

Ring-opening reaction via selective cleavage of C–C bond is a powerful strategy to increase molecular complexity. Here the authors present the facile synthesis of chiral 1,5- and 1,6-dinitriles via the radical-mediated ring-opening and enantioselective cyanation of cycloketone oxime esters.

Summary: The direct functionalization of C(sp3)-H bonds has led to the development of methods to access molecules or intermediates from basic chemicals in an atom- and step-economic fashion. Nevertheless, achieving high levels of chemo-, regio-, and enantioselectivity in these reactions remains challenging due to the ubiquity and low reactivity of C(sp3)-H bonds. Herein, we report an unprecedented protocol for enantioselective cyanation of remote C(sp3)-H bonds. With chiral Box-Cu complex as the catalyst, the reaction of N-fluorosulfonamide furnishes the corresponding products in excellent yields and high enantiomeric excess (ee) under mild reaction conditions. A radical relay pathway involving 1,5-hydrogen atom transfer (1,5-HAT) of N-center radicals followed by enantioselective cyanation of the in situ-formed benzyl radicals is proposed. This enantioselective copper-catalyzed cyanation thus offers insights into an efficient way for the synthesis of bioactive molecules for drug discovery. : Catalysis; Organic Synthesis; Stereochemistry Subject Areas: Catalysis, Organic Synthesis, Stereochemistry

The catalytic C(sp3)-CF2 bond formation is of high interest in drug design and discovery. Here, the authors report a cobalt-catalyzed difluoroalkylation of tertiary α-C-H bonds of aryl ketones for facile synthesis of quaternary alkyl difluorides and show the late-stage functionalization of marketed drugs.

Prostate cancer is the major cause of cancer-related deaths worldwide in men. There are new treatment methods and drugs are being developed with promising results in two of the prostate cancer cell lines (PPC-1 and TSU-Pr1). These two cells were treated with 20 uM of axitinib combined with dasatinib for 6-72 hours. The cell viability assessed by the cytotoxicity assay. Various regulatory genes such as c-KIT, cell cycle and apoptosis and angiogenic factors were also studied. The enzyme activity of apoptosis effector caspase-3 was colorimetrically determined. Axitinib and dasatinib combination lowered the survival rate of PPC-1 cells but enhanced the survival rate of TSU-Pr1 cells. The protein expression levels in apoptosis and angiogenesis factors were also found to be in contrast between the two cell lines. PPC-1 and TSU-Pr1 cells displayed a different response to axitinib with dasatinib, which explains different expression levels of regulators of cell-cycle, apoptosis and angiogenesis.

An oxidative cleavage of C-C double bonds of enamides promoted by hypervalent iodine(III)/TMSN3 under an air atmosphere is developed. This reaction provides a new approach to construct various cyanobenzamides, which offers further synthetic potential for the preparation of industrial and pharmaceutical nitrogen- and oxygencontaining molecules, and exhibits good functional group tolerance, broad substrate scope and mild conditions. [ABSTRACT FROM AUTHOR]

A neutral metal-free system for the head-to-tail dimerization of electron-rich alkenes with stoichiometric amount of BrCCl2H and NaI is reported. This reaction proceeds under mild conditions with high efficiency and broad scope. [ABSTRACT FROM AUTHOR]

The article discusses a study on the incorporation of fluorine atoms into small organic molecules, enhancing the metabolic stability, lipophilicity, and bioavailability. It notes that fluorine-containing compounds have been used in pharmaceutical and agrochemical products, and that the selective introduction of monofluoromethyl groups into small organic molecules has come out as a strategy in drug design.

Prostate cancer is major cause of cancer related deaths worldwide in men. There are new treatment methods and drugs are being developed with promising results in two of the prostate cancer cell lines (PPC-1 and TSU-Pr1). These two cells were treated with 20 uM of axitinib combined with dasatinib for 6-72 hours. The cell viability assessed by the cytotoxicity assay. Various regulatory genes such as c-KIT, cell cycle and apoptosis and angiogenic factors were also studied. The enzyme activity of apoptosis efector caspase-3 was colorimetrically determined. Axitinib and dasatinib combination lowered the survival rate of PPC-1 cells but enhanced the survival rate of TSU-Pr1 cells. The protein expression levels in apoptosis and angiogenesis factors were also found to be in contrast between the two cell lines. PPC-1 and TSU-Pr1 cells displayed a different response to axitinib with dasatinib, which explains different expression levels of regulators of cell-cycle, apoptosis and angiogenesis. [ABSTRACT FROM AUTHOR]