Oxime-based palladacycles

Cyclometallated iridium complexes, for OLEDs, 12, 145 Cyclometallated palladium(II) complexes from amines and pyridines, 8, 280 with C,C-chelating ligands, 8, 291 enantioselective synthesis, 8, 296 ferrocene-based palladacycles, 8, 292 four-membered palladacycles, 8, 297 imine- and oxime-based complexes, 8, 285 with N-N and N=N bonds, 8, 288 palladacycle catalysis, 8, 297... 

More recently, Najera et al. performed a number of Heck reactions of deactivated aryl halides and styrenes under phosphane-free conditions using oxime-derived palladacycles or palladium acetate as catalyst [113], Coupling can be performed either vith chcyclohexylmethylamine as base and TBAB as PTC catalyst or in neat vater vith triethylamine in N,N-dimethylacetamide (DMA) solutions under the action of MW irradiation. 

Ramesh et al. synthesized a cyclometallated dimeric palladium) ) catalyst with covalently bonded based on the concept that release slowly the highly active species from structurally more stable catalyst precursors [110]. By utilizing this dimeric oxime-type palladacycle as the catalyst, various aryl iodides were reacted with aliphatic alcohols and phenols in a highly selective manner and gave the corresponding esters in excellent yields. Based on these excellent yields, apparently no by-products were formed. Remarkably, the complex was stable even at high temperatures (120 °C) and under 10 bar of carbon monoxide. 

Sonogashira reaction. The first system consisted in the use of the oxime palladacycles 7a-f at elevated temperatures, without the aid of Cul or an amine base, for the coupling of aryl iodides and bromides. They also reported on the use of complex 48b in aqueous media for the coupling of aryl iodides and bromides and terminal acetylenes in excellent yields. ... 

A lot of trivial nitrogen-containing compounds (Schiff bases, oximes and benzylamines) readily form palladacycles. These are invariably useful precatalysts for Mizoroki-Heck... 

In 2011, a palladium-catalyzed ojyarylation of dihydronaphthalene and chromenes with o-iodophenols and its acetates was developed. The OTty-atylation of dihydronaphthalene, two electron-rich and one electron-poor chromenes with different o-iodophenols and their acetates has been investigated by using either Pd(OAc)2 (10 mol%) as a precatalyst and Ag2C03 as a base in acetone as a solvent or oxime palladacycle as a precatalyst and dicyclohejylamine as a base in DMA-H2O. The reactions, which were... 

Dinuclear cyclometallated palladium(ii) complexes 81 have been obtained from Schiff base ligands. Cyclopalladated complexes of oximes 82 and 83 and their ligand-exchange reactions have been studied. Ketoximes form palladacycle dimers such as 84. " ... 

A-Heterocycles were synthesized via insertion of 1,1-dimethylallene into Pd-G bonds of cyclopalladated a-tetralone ketimines. Insertion reactions of alkynes into the Pd-G bond of cyclopalladated ferrocenylimines have also been described.Biomimetic hydrolysis of benzoates has been carried out with a water-soluble cyclopalladated aryl oxime, which was proposed as a potential green catalyst. Ghiral cyclopalladated liquid crystals 88 were obtained from amino acids and could possibly serve as enantioselective catalysts. " Palladacycle 89 has been derived from an anthracene-based Schiff base. 

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