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A synthetic route for the preparation of alkynylated saturated N‐heterocycles via a sequential combination of a Shono oxidation and a gold(I)‐catalyzed alkynylation reaction has been developed. The electrochemical Shono oxidation allowed an efficient access to a variety of N,O‐acetals via a direct C−H bond functionalization of cyclic amines. The reaction conditions were amenable with functionalized pyrrolidine, tetrahydroisoquinoline and pyrrolidine‐cyclopropyl fused bicyclic skeletons. The gold‐catalyzed process allowed the introduction of aryl acetylene partners bearing electron‐donating and moderate electron‐withdrawing. The efficiency of the gold process is remarkable and could be scaled up to 5 mmol of N,O‐acetal. Post‐functionalization reactions were performed based on the reactivity of the alkyne, showing the broad interest of our methodology. Promising preliminary results on an asymmetric version were obtained (e.r. up to 84.5:15.5). [ABSTRACT FROM AUTHOR]

Exploiting trimethylsilyltrifluoromethanesulfonate as Lewis acid, (hetero)aromatics underwent regioselective and direct carbamoylation. The method is based on the in situ generation of a highly electrophilic carbamoyl triflate active species. TMSOTf acts as Lewis acid to activate carbamoyl chlorides and generates highly electrophilic carbamoyl triflates in situ; these are active species for late‐stage aromatic carbamoylation. [ABSTRACT FROM AUTHOR]

Merging the latest advances in the field of gold catalysis and the efficiency of hexafluoro‐2‐propanol (HFIP), a gold‐catalyzed orthogonal tandem reaction has been developed to access carbocyclic ketone on naphthalene substrates. The methodology involved a cycloisomerization/nucleophilic addition and a C→O rearrangement. The HFIP solvent most probably acted as a Lewis‐acid on isochromene derivatives, through hydrogen donor bond activity. A large range of acenaphthylene carbaldehyde has been engaged in this process coupling gold catalysis and Lewis‐acid behavior of HFIP leading to cyclic ketones with a yield ranging from 15 to 91% (27 compounds). The mechanism was investigated, and the reaction most presumably occurred via a classical cyclization process followed by a [Au]‐HFIP interaction for the final rearrangement. The interest of such transformation was demonstrated by performing it on a gram‐scale. Moreover, a post‐functionalization bromination was performed, as well as the isomerization of some functionalized ketones leading to full trans derivatives with a yield ranging from 78 to 90% yields. [ABSTRACT FROM AUTHOR]

The preparation of new electrolytes for application in lithium or sodium batteries is described. Different salts of lithium and sodium sulfonamide and bis(sulfonyl)imide were prepared in good yields. Ionic conductivity measurements were performed on these salts and conductivities of 0.20 to 0.51 mS cm−1, comparable to those of Li-TFSI, were obtained. The best conductivity was reached for the Li+ salt of a bis(sulfonyl)imide bearing CF3 and 4-FC6H4 groups. [ABSTRACT FROM AUTHOR]

Abstract: We have developed a procedure for the preparation of anhydrous metallic triflates and triflimidates of general formulae M(OTf) n and M(NTf2) n based on the oxidative dissolution of metal powders in the presence of HOTf or HNTf2, respectively. The method provides salts in anhydrous form, solvates with DMSO molecules, and constitutes a good complement to a previous method developed in our group based on an electrochemical procedure. We have compared the catalytic activity of various Sn(IV) salts in the reaction of cycloisomerisation of 1,6-dienes and identified that anhydrous Sn(IV) triflimidates are more active catalysts, as compared to anhydrous Sn(IV) triflate, or their hydrated forms usually obtained by conventional methods of preparation or purchased from chemical suppliers. [Copyright &y& Elsevier]

The intramolecular electrochemical reductive cyclization of ortho‐haloaryl allyl thioethers catalyzed by Ni(II) complexes associated to cyclam ligands affords dihydro‐benzo[b]thiophene derivatives in moderate to good yields. #Dedicated to Pr. E. Dinjus for its 60th anniversary. [ABSTRACT FROM AUTHOR]

(R)‐Limonene, a renewable terpene, and its epoxidized derivatives, i. e. limonene epoxides, have prompted growing attention over the last decade as building blocks for the synthesis of biobased monomers and polymers. With the goal of replacing petroleum‐based polymers several polymerization techniques have been applied on limonene oxide and limonene dioxide monomers. This paper aims to contribute to the literature by presenting a review dedicated to limonene oxide and dioxide as raw monomers of renewable origin for the development of biobased polymers. The polymerization techniques described are namely the homopolymerization, the copolymerization with carbon dioxide and anhydrides, and the copolymerization of limonene epoxide‐based monomers. Limonene oxide polymerizations will be investigated first, followed by limonene dioxide polymerizations. [ABSTRACT FROM AUTHOR]

Mg in catalytic amounts as the only metal permits the reductive coupling between benzyl halides and pinacolborane. HBpin acts both as an electrophile and as a reducing agent to regenerate an organomagnesium species in situ. An hydride oxidation mechanism is proposed on the basis of DFT calculations. [ABSTRACT FROM AUTHOR]

Several oxaspirocyclic ethers were prepared under heterogeneous catalytic conditions from polyfunctional alcohols with tethered olefinic double bonds. Good yields and efficient catalyst recycling tests were obtained with Amberlyst-15. [ABSTRACT FROM AUTHOR]

Acenaphthylene carbaldehyde, tandem reaction, gold, C->O Rearrangement, HFIP Front Cover Picture: Gold-Catalyzed One-Pot Cycloisomerization/Nucleophilic Addition/Rearrangement of Acenaphthylene Carbaldehyde Derivatives (Adv. Keywords: Acenaphthylene carbaldehyde; tandem reaction; gold; C->O Rearrangement; HFIP EN Acenaphthylene carbaldehyde tandem reaction gold C->O Rearrangement HFIP 1907 1907 1 06/30/23 20230620 NES 230620 The front cover picture is an artistic illustration of gold associated with HFIP, represented by a golden ball surrounded with a banner. [Extracted from the article]

This review concentrates on the intramolecular cyclizations of organic halides catalyzed by nickel complexes using an electrochemical methodology, as an alternative to the classical radical or transition-metal catalyzed or mediated processes. [ABSTRACT FROM AUTHOR]

We report a new synthetic strategy for single Li-ion conducting solid polymer electrolytes based on the fully aromatic polymer poly(ether ether ketone) (PEEK) grafted with differently substituted bis(sulfonyl)imide groups for use in lithium metal and lithium-ion batteries. The preferred polymer contains no fluorine and is particularly advisable from an environmental point of view. Its ionic conductivity reaches 0.03 mS cm−1 at 65 °C. [ABSTRACT FROM AUTHOR]

A series of metal sulfonate salts attached to a poly(ether ether ketone) (PEEK) polymer were prepared by ultrasonic activation and then examined as heterogeneous catalysts in the Friedel-Crafts acylation of aromatic derivatives. [ABSTRACT FROM AUTHOR]

This study valorises the benign epoxidation of (R)-(+)-limonene to generate novel bio-resourced limonene dioxide monomers. Without additional steps of separation or functionalization, the racemic limonene dioxide was cured with glutaric and dimethylglutaric anhydrides leading to thermosets with a high Tg (∼98 °C) and good mechanical properties (σ = 27 MPa; ε = 3.5%; E = 1150 MPa; E′ = 1650 MPa, Shore D = 78). [ABSTRACT FROM AUTHOR]

Abstract: The electroreduction of allylic halide derivatives in the presence of pinacolborane afforded allylboronic pinacol esters with moderate to good yields (up to 86%) and high regioselectivities. The electrosynthesis was carried out in a single-compartment cell with an Al anode, in THF at room temperature and it constitutes an alternative route for the preparation of allylboronic esters under mild conditions. [Copyright &y& Elsevier]

A series of metallic tosylates were prepared by ultrasonic metal activation and were further used as efficient catalysts for the acylation of aromatic derivatives. [ABSTRACT FROM AUTHOR]

Metal salts of triflic acid, CF3SO2OH and of triflimidic acid, [CF3SO2]2NH, often called 'Lewis superacids', are powerful catalysts for several classes of reactions. Typical applications developed at the Institut de Chimie de Nice during the last decade, mostly in the domain of inter- and intramolecular carbon-carbon, carbon-oxygen and carbon-sulfur bond formation, are illustrated. During the last three years, the characterization of metal triflates and triflimides by electrospray mass spectrometry was also accomplished in our Institute. Displacement of one anion of the salt by strong neutral ligands was developed as a mean for generating characteristic positive ions. In an effort toward the quantitative description of the ligand/metal bonding and the catalytic role of the Lewis acid, a ligand competition method was devised. An exploratory study attests that subtle structural effects on the donor/acceptor interaction can be evidenced using this simple mass spectrometric method. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The interaction between two Lewis 'superacid' catalysts Zn(OTf) and In(OTf) and series of amide and phosphate ligands is quantitatively characterized by electrospray ionization mass spectrometry (ESI-MS). A specific feature of the ESI-MS spectra of the mixture of metal triflates and Lewis bases is the formation of ionic adducts resulting from the displacement of one triflate anion by two neutral ligands. A ligand competition model is developed, which describes the relative intensities of the ionic adducts as a function of relative ligand concentrations. The relative affinities deduced from the ligand competition method are combined in an affinity scale for the metal triflate. [ABSTRACT FROM AUTHOR]

Abstract: The electrochemical reductive cyclisation of unsaturated organic halides in the presence of Ni(II) complexes as catalysts was examined in aprotic solvents such as DMF and in protic solvents such as ethanol, butanol or ethanol–water mixtures. The presence of the alcohol media enhanced the rate of recycling of the catalytic species. [Copyright &y& Elsevier]

The relative Lewis basicity of a series of phosphoryl compounds toward cations Mn+(OTf)n−1derived from triflate salts, M(OTf)n, is ranked using electrospray mass spectrometry according to competitive adduct formation. [ABSTRACT FROM AUTHOR]

An abstract of the article "Catalysis of the acylation of aromatic derivatives by metallic tosylates," by V. Morizur and colleagues is presented.