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Despite the progress on cobalt and manganese catalyzed C−C and C−N bond‐forming methodologies, the associated catalyst reusability remains with some unresolved issue, which needs to be addressed. Disclosed herein, a flexible multidentate proton‐responsive ligand (L) bearing 2,6‐bis(1H‐benzo[d]imidazol‐2‐yl)pyridine (BBP), 6‐(1H‐benzo[d]imidazol‐2‐yl)picolinic acid (BPA), and benzene‐1,2‐diamine (BDA) for Co/Mn‐based mono‐ and bi‐metallic supramolecular materials for C‐/N‐alkylation of alcohols. The flexible binding sites and different hydrogen bond donor‐acceptor fragments of L brings the rigidity and self‐assembling to ordered crystalline supramolecular materials, which prevented the coordinatively saturated active sites and thus providing much higher reaction efficiency and selectivity, which is highly unlikely in the case of comparable individual components. The easy synthesis, efficient reactivity and selectivity through cooperativity, broad substrate scope, and efficient recycling via recharging of metals make the catalyst and the protocol economical and sustainable. Importantly, the design strategy based on metallo‐organic hydrogen bonded coordination assembly has the potential to contribute to the development of supramolecular materials for various advanced catalytic applications. [ABSTRACT FROM AUTHOR]

Herein, we disclose a selective, versatile, accessible, cost‐effective and highly efficient cation‐exchange industrial grade INDION 130 resin as a reusable catalyst for the synthesis of 3‐substituted isoindolinones from various γ‐hydroxy lactams and a variety of C, N, O, and S nucleophiles involving N‐acyliminium ion intermediates under mild reaction conditions. Mechanistic studies suggested the generation of a different kind of kinetically and thermodynamically controlled intermediates/eliminated products, which further converted to their corresponding products depending upon the nucleophile, reaction parameter and nitrogen substitution (benzyl vs. aryl) of the substrate (succinamidals vs. phthalimidals). The easy synthesis, efficient reactivity and selectivity, broad substrate scope with verities of C, N, O, and S nucleophiles, and efficient recycling make the catalyst and the protocol economical and sustainable. [ABSTRACT FROM AUTHOR]

The 1-iridaindene complex, Ir[C.sub.8][H.sub.5]Cl[(P[Ph.sub.3]).sub.2] (2), has been prepared from the reaction of IrCl[(P[Ph.sub.3]).sub.3] with PhC ≍ CPh by a novel direct cycloiridation reaction. A plausible mechanistic pathway has been suggested involving π-coordination assisted ortho- C-H activation and subsequent alkyne hydroiridation reaction to provide the five-member iridacycle. Key words: iridium, diphenylacetylene, C-H activation, cyclometallation, metallacycle. On a prepare le complexe du 1-iridaindene, Ir[C.sub.8][H.sub.5](ph-2)]Cl(P[Ph.sub.3])2 (2), par reaction du IrCl[(P[Ph.sub.3]).sub.3] avec le PhC ≍ CPh par une nouvelle reaction de cycloiridation directe. On propose une voie mecanistique plausible impliquant une activation du C-H en ortho qui serait assistee par une coordination π et qui serait suivie par une reaction d'hydroiridation de l'alcyne conduisant a la formation de l'iridacycle a cinq chainons. Mots-cles : iridium, diphenylacetylene, activation d'une liaison C-H, cyclometallation, metallacycle. [Traduit par la Redaction] Choudhury et al. 187, Introduction Metallacycles are important synthons as well as intermediates in many catalytic organic and organometallic reactions (1-12). Iridaindene motifs can be viewed as metallacyclopentadienes that are intermediates in metal-mediated [2+2+2] [...]

A discrete, photoactive, ultrafine copper nanocluster of fewer than hundreds of atoms with stimuli‐responsive switchable redox‐active states is highly desired to control two different antagonistic reactions. Herein, a mixed‐valent tetrametallic copper complex (C‐1) of N−O‐N Schiff base ligand is disclosed, in which the five different Cu−Cu interactions were used to generate photoactive nanoscale copper [LCu0n, S‐1] through the reduction of coordinated imine to the amine of C‐1. The presence of a ligand provides stability and helps to homogenize the material (S‐1) in the organic solvent. The cluster showed stimuli (O2/light)‐responsive switching between its reduced (S‐1) and oxidized [LCu0n−mCuOm, S‐2] states that allows it to serve as a highly and poorly active (bistate, relative rate >5–12 fold) catalyst for the dehydrogenation of alcohols to aldehydes and hydrogenation of nitroaromatics to amino aromatics under the light. [ABSTRACT FROM AUTHOR]

Herein we disclosed the use of a remote ‘imidazole’‐based precatalyst [(para‐cymene)RuII(L)Cl]+, C‐1 where L=2‐(4‐substituted‐phenyl)‐1H‐imidazo[4,5‐f][1,10] phenanthroline) for the selective oxidation of a variety of alkyl arenes/heteroarenes and alcohols to their corresponding aldehydes or ketones in presence of tert‐butyl hydroperoxide (TBHP). The remote ‘imidazole’ moiety present in the complex facilitates the activation of oxidant and subsequent generation of active species via the release of para‐cymene from C‐1, which in‐turn was less effective without the ‘imidazole’ moiety. The mechanistic features of C‐1 promoted oxidation of alkyl arenes were also assessed from spectroscopic, kinetic, and few control experiments. The substrate scope for C‐1 promoted oxidation reaction was assessed based on the selective oxidation of 27‐different alkyl arenes/heteroarenes and 25 different alcohols to their corresponding aldehydes/ketones in moderate to good yields. [ABSTRACT FROM AUTHOR]

The nucleophilicity values of the commonly used arenes and heteroarenes are calculated by using the inverse concept of electrophilicity and nucleophilicity and with four different available equations for electrophilicity and electrodonating power. Four different arene and heteroarene series are subjected to local nucleophilicity analysis in order to predict the site selectivity in electrophilic aromatic substitution reactions (EAS).