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A novel convenient "one-pot" synthesis of 2-oxo-1,2λ 5 -azaphosphacyclanes 1 and 1,2λ 4 -azaphosphacyclanium salts 2 via intramolecular N-alkylation of ω-halogenalkyl-substituted iminophosphoryl compounds 3 has been developed. The common nature of the reaction of intramolecular cyclization of iminophosphoryl compounds having an alkoxy group at the phosphorus atom and the Arbuzov reaction has been established. [ABSTRACT FROM AUTHOR]

Abstract: Water as a solvent significantly accelerates the addition of various amines to diethyl vinylphosphonate to yield β-aminophosphonates without any catalyst compared to known procedures for such aza-Michael reactions. The products are obtained in quantitative yields and high purity over short reaction times. Using a reactant ratio (vinylphosphonate/amine) of 2:1 resulted in double phosphorylation of primary amines. [Copyright &y& Elsevier]

Room-temperature imidazolium ionic liquids [Rmim][X] (X=Br, BF4, NTf2) as a reaction medium change the reaction course of phosphorus(III) acid esters with primary alkyl halides, aryl bromides, and propargyl bromide to afford hydrophosphoryl compounds, products of oxidation of the starting phosphorus substrates, and 2,3-bis(phosphoryl)prop-1-enes, respectively. [Copyright &y& Elsevier]

Abstract: A series of novel hybrid pincer ligands bearing thiophosphoryl and imino groups as donating arms was obtained by the condensation of 3-diphenylthiophosphorylbenzaldehyde with RNH2 (R = Ph, tBu) to afford aldimine derivatives 2a, b or by the reaction of lithiated 3-(thiophosphoryl)bromobenzene with an appropriate substituted lactam yielding their ketimine analogs 2c–e with 5–7-membered azacycloalkene moieties. The direct cyclopalladation of the ligands with (PhCN)2PdCl2 in MeCN under reflux led to κ3-NCS pincer complexes 3b–e with two five-membered fused metallacycles, isolated in low to moderate yields (12–53%); their structures were confirmed by multinuclear NMR and X-ray diffraction study. The palladacycles demonstrated high activity as (pre)catalysts for the Suzuki cross-coupling of phenylboronic acid with aryl bromides, which was found to increase in the series 3e ∼ 3d <3c< 3b, i.e. passing from ketimine derivatives 3d, e with larger azacycloalkene to their analog with smaller five-membered cyclic imine moiety and further to benzaldimine complex 3b. The tendency observed was explained by the controlled release of Pd(0) catalytically active species in the case of less sterically hindered complexes. [Copyright &y& Elsevier]

Abstract: Biphasic systems room temperature imidazolium ionic liquid (RTIL)/water or water as a solvent significantly accelerate the addition of amines to vinylphosphoryl compounds hence opening green and effective synthesis of β-aminophosphoryl compounds in excellent yields over short reaction times. The application of water, being the cheapest and most non-toxic solvent, without any catalyst or co-solvent, is more advantageous as it provides a simple isolation procedure for products having high purity (>95% according to the NMR data) via simple freeze-drying and does not require extraction with organic solvents. The solubility of the starting phosphorus substrate in water does not play crucial role in the reaction as it was demonstrated using water insoluble diphenylvinylphosphine oxide. In contrast to typical procedures, using a reactant ratio (vinylphosphoryl compound: amine) of 2:1 readily resulted in double phosphorylation of primary amines, including polyamines, in water. [Copyright &y& Elsevier]