A general and simple nickel-catalyzed coupling of aryl chlorides amines is reported. The scope limitations the process using Ni(0), 1,3-bis(2,6-diisopropylphenyl)dihydroimidazol-2-ylidene, NaO-t-Bu as base were investigated. Secondary cyclic acyclic anilines provided arylamine products in good to excellent yields. Compared palladium-catalyzed aminations, this procedure offers an alternative route N-substituted starting from readily available chlorides.

The use of an in situ generated Ni(0) catalyst associated with 2,2'-bipyridine or N,N'-bis(2,6-diisopropylphenyl)dihydroimidazol-2-ylidene (SIPr) as a ligand and NaO-t-Bu the base for intramolecular coupling aryl chlorides amines is described. procedure has been applied to formation five-, six-, seven-membered rings.

The incorporation of chloro, fluoro, or methoxy substituents on the pyridine ring pyridyltrimethylsilanes allowed us to perform efficient Hiyama cross-coupling with various (het)aryl halides. reactions proceeded smoothly at room temperature leading corresponding functional bis(het)aryl in fair excellent yields. presence nitrogen alpha trimethylsilyl group was requisite achieve cross-coupling. [Reaction: see text]

This work presents a new synthesis of nano-sized lithium niobate particles by low temperature three steps procedure. The complete protocol implies LiH induced reduction NbCl5 followed in situ spontaneous oxidation into valence niobium nano-oxides. These oxides are exposed to air atmosphere leading pure Nb2O5 formation. Finally, the stable is converted LiNbO3 nanoparticles during controlled hydrolysis excess. as well their formation processes were characterized using X-ray photoelectron spectroscopy.

Dehalogenation of aryl halides was efficiently performed in refluxing THF using a catalytic combination composed Ni(0)/N-heterocyclic carbene (NHC)/β-hydrogen-containing alkoxide. IMes·HCl (1,3-bis(2,4,6-trimethylphenyl)imidazolium chloride) and Ni(acac)2 used respectively as Ni(0) precursors associated to situ generated i-PrONa were found be the most effective for dehalogenation functionalized chlorides, bromides, iodides, polyhalogenated hydrocarbons.

Transfer hydrogenation of imines to the corresponding amines by Et2CHONa catalyzed monocoordinate Ni(0)/N-heterocyclic carbene species Ni(0)/IMes has been studied. Using this catalyst, a variety aldimines and ketimines were reduced in good excellent yields under mild conditions.

Abstract Monocoordinate nickel/ N ‐heterocyclic carbene complexes reveal unexpected reactivity towards aryl fluorides. Defluorination reactions were efficiently performed with a β‐hydrogen‐containing alkoxide (3 equiv.) in the presence of 3 mol % [1:1] Ni(0)/IMes⋅HCl catalyst (IMes=1,3‐dimesitylimidazol‐2‐ylidene).

Abstract This account covers the current status of pyridine metallation with alkyllithium/lithium aminoalkoxide reagents and follows a previous review focusing on pioneering works n BuLi/LiDMAE reagent. An updated overview scope this superbase is presented, together development new synthetic applications based selective lithiation methodology.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

nBuLi/lithium aminoalkoxide aggregates have proven to be useful new lithiating agents. This review covers the current status of authors' works on direct metallation pyridine derivatives with these reagents, featuring scope their synthetic potential. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)

Abstract Finely dispersed Ni powders were obtained after chemical reduction of Ni(II) salts by activated sodium hydride in organic solvents. This process allows one to prepare particles the nanometre range. The with sizes smaller than 4nm found be hcp whereas larger fcc. To best our knowledge, this is first observation that unsupported powder may crystallize system and phase stability metallic element particle size dependent.

The reaction of 2-chloropyridine with alkylithium generally results in nucleophilic addition leading to the loss chlorine atom while exclusive directed ortho metalation is obtained using LDA. Herein it shown that BuLi-Me(2)N(CH(2))(2)OLi (BuLi-LiDMAE) superbase promotes an unprecedented regioselective C-6 lithiation. method was successfully applied preparation potentially useful chlorinated pyridinic and bis-heterocyclic synthons.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTActivation of reducing agents. Sodium hydride containing complex 33. NiCRA's and NiCRAL's as new efficient desulfurizing reagentsSandrine Becker, Yves Fort, Regis Vanderesse, Paul CaubereCite this: J. Org. Chem. 1989, 54, 20, 4848–4853Publication Date (Print):September 1, 1989Publication History Published online1 May 2002Published inissue 1 September...

A series of potential unimetal superbases BuLi–ROLi has been studied in order to increase the basicity/nucleophilicity ratio ([B/N]R) BuLi. The best [B/N]R is found with BuLi–LiDMAE. This complex base apparently metallates 2-methoxypyridine at unexpected C-6 position. It shown that no actual metallated species are formed reaction medium, occurring as result a common radical precursor stabilized by an aggregate cluster. Finally, application, substituted 2-methoxypyridines have obtained good...

The first direct α-lithiation of 4-DMAP has been peformed via reaction with the BuLi−Me2N(CH2)2OLi (BuLi−LiDMAE) reagent. This new methodology avoids use a activation−lithiation−regeneration sequence or halogen−metal exchange classically employed. New useful DMAP-containing synthons and polyheterocycles have efficiently prepared.