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New nickel‐based complexes of 1,2‐bis[(2,6‐diisopropylphenyl)imino]acenaphthene (dpp‐bian) with BF4− counterion or halide co‐ligands were synthesized in THF and MeCN. The nickel(I) complexes were obtained by using two approaches: 1) electrochemical reduction of the corresponding nickel(II) precursors; and 2) a chemical comproportionation reaction. The structural features and redox properties of these complexes were investigated by using single‐crystal X‐ray diffraction (XRD), cyclic voltammetry (CV), and electron paramagnetic resonance (EPR) and UV/Vis spectroscopy. The influence of temperature and solvent on the structure of the nickel(I) complexes was studied in detail, and an uncommon reversible solvent‐induced monomer/dimer transformation was observed. In the case of the fluoride complex, the unpaired electron was found to be localized on the dpp‐bian ligand, whereas all of the other nickel complexes contained neutral dpp‐bian moieties. [ABSTRACT FROM AUTHOR]

ABSTRACT A number of chiral racemic and enanthiopure thiophosphorylated thioureas were synthesized by the reaction of 2-aminobutan-1-ol and 1-(a-aminobenzyl)-2-naphthol with O, O-diethyl thiophosphoryl isothiocyanate. It was found that such thioureas undergo the cyclization reaction under basic conditions with hydrogen sulfide elimination and the formation of thiophosphorylated oxasines. X-Ray single crystal diffraction revealed that the structure of thiourea is close to the prereaction state of the cyclization reaction. [ABSTRACT FROM AUTHOR]

A new diastereoselective synthesis of α-aminophosphonates has been developed, based on the reaction of trialkyl phosphites with a chiral imines, derived from (R)- or (S)-1-(α-aminobenzyl)-2-naphthol, in the presence of trifluoroacetic acid. The major diastereomer of obtained aminophosphonates can be separated by crystallization from an appropriate solvent. The desired α-aminophosphonic acids can be obtained in enantiopure form by treating the corresponding diastereomers with HCl. [ABSTRACT FROM AUTHOR]

Stable phosphonium salts were synthesized by the phosphorylation of a series of ω-haloalkylcarboxylic acids with triphenylphosphine. In a second step the resulting phosphonium salts have been treated with 1 M aqueous solution of sodium hydroxide to form the corresponding carboxylate phosphabetaines. The structure of the isolated compounds was determined by IR and NMR spectroscopy, elemental analysis, and X-ray crystallographic studies. Their thermal stability was studied by simultaneous thermogravimetry and differential scanning calorimetry. [ABSTRACT FROM PUBLISHER]

A novel phosphorylation reaction of dichlorodinitrobenzofuroxan by triphenylphosphine has been studied. An unusual course of the reaction with the participation of benzofuroxan nitro groups as reactive centers has been established. It is shown that as final product of the reaction, a stable diphenolate diphosphabetaine with strong participation of the mesomeric ketoylide structure is formed. The structure of the product has been confirmed by X-ray diffraction. [ABSTRACT FROM AUTHOR]

[1,1';3',1'']Terphenyl-4',5'-dicarboxylic acid derivatives were prepared from 1,3-dienic δ-sultone 4,6-diphenyl-[1,2]oxathiine 2,2-dioxide via Diels-Alder/retro-Diels-Alder reaction with dimethyl acetylenedicarboxylate under thermal, microwave or high-pressure activation. [ABSTRACT FROM AUTHOR]

A synthetic protocol for optically pure (-)-menthylamine, (-)-8-methylmenthylamine, and the novel (-)-8-phenylmenthylamine is presented including a detailed characterization of these compounds and their isocyanates. Key words: amines; aminations; asymmetric synthesis; chirality; chiral auxiliaries. [ABSTRACT FROM AUTHOR]

The chlorination of electron rich iodoarenes with MoCl[sub5] proceeds with methoxycarbonylmethyl as the directing group. The transformation is selective and without loss of the valuable iodo substituent. [ABSTRACT FROM AUTHOR]

We developed a new approach to the synthesis of saturated and unsaturated phosphoruselementocontaining heterocycles was developed; we based it on the addition reactions of various proton nucleophiles (amines, silylamines, alcoholes, mercaptanes, aminoalkylphosphonates, phosphines, CH-acides, etc.) to the halogenmethylphosphonylated isocyanates or isothiocyanates. Intermediate compounds of these reactions (phosphorylated ureas, thioureas, urethanes, thiouretanes, acylamides, etc.) are easily transformed into phosphorus containing cyclic structures. [ABSTRACT FROM AUTHOR]

The PBu 3 -catalyzed conjugate addition of diphenylphosphine oxide to unsubstituted and substituted electron-deficient alkenes is reported. β-Substituted α,β-unsaturated esters, trans -methyl crotonate and trans -methyl cinnamate, known for their reluctance to participate in phosphine-catalyzed transformations, also react well under the developed conditions. Mild reaction conditions, simple work-up and the ease of catalyst recovery make the proposed methodology useful for the preparation of functionalized tertiary phosphine oxides. The utility of this method was demonstrated by the gram-scale reactions of diphenylphosphine oxide with electron-deficient alkenes. [ABSTRACT FROM AUTHOR]

An efficient PBu 3 -catalyzed α-addition of the P(O)–H bond to ethyl phenylpropiolate has been developed. This strategy offers a facile method for the preparation of synthetically useful alkenyl phosphonates and phosphinates proceeding under neutral reaction conditions with high atom economy. [ABSTRACT FROM AUTHOR]

The two new nickel complexes [Ni(P R 2 N Ph(CH)Ph 2 ) 2 ] 2+ (where R = Ph or o -Py) with cyclic 1,5-diaza-3,7-diphosphacyclooctane ligands have been synthesized. All complexes are effective electrocatalysts for hydrogen production using [(DMF)H] + as proton source in acetonitrile. The bulky benzhydryl substituent at nitrogen atom leads to higher catalytic activity comparison to benzyl. The introduction o -Py substituents at phosphorus as additional basic center is caused by the changing of voltage–current picture and significantly catalytic current enhancement. TOFs being 100 and 15200 s −1 for R = Ph and o-Py, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Alkylation of γ- and δ-sultams with (iodomethyl)trimethylsilane followed by treatment of the resultant silanes with tetrabutylammonium fluoride gave rise to sulfur-free unsaturated amines. In particular, N-THP substituted sultams were found to be useful substrates for the alkylation event. A corresponding one-pot transformation involving sultam α-alkylation with (iodomethyl)magnesium chloride is also reported. [Copyright &y& Elsevier]

A new type of stereospecific cascade cyclization was observed in the phosphorylation reaction of N,N’-bis(salicylidene)ethylenediimine with alkylenechlorophosphites, which resulted in the formation of tetracyclic hexacoordinated phosphorus derivatives containing the P–C–N fragment with a chiral carbon atom in the α-position to phosphorus. [Copyright &y& Elsevier]

The optimized reaction conditions allow the regio- and stereoselective synthesis of alkenyl phosphonates. [ABSTRACT FROM AUTHOR]