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Clathrochelate Iron(II) α-Dioximates containing macrocyclic bicursors undergo a smooth phosphorylation reaction to yield (thio)phosphorylated monoribbed-functionalized iron(II) mono- and bis-clathrochelates [ABSTRACT FROM PUBLISHER]

A convenient one-pot synthesis of N-phosphoryl-2-oxo-1,2-azaphospholanes was developed starting from commercially available or simple-to-prepare phosphorus (III) acid chlorides and 3-bromopropylamine. The compounds readily form complexes with f-elements of ML, ML2, and M2L3 composition including (μ2-peroxo)-bridged uranium complexes, depending on both the ligand and metal nature. [ABSTRACT FROM AUTHOR]

Abstract: The synthetic approach to the novel cyclic (S)PNP(S) ligands ▪ (5a–c, R=EtO, Me, Ph), i.e. 1-thiophosphoryl-2-thioxo-1,2-azaphospholanes having different surrounding at the exocyclic phosphorus atom, has been developed. Compounds bearing two asymmetric phosphorus atoms were obtained as individual (R ∗,R∗ )- and (R∗ ,S ∗)-diastereomers. Reacting with (PhCN)2MCl2 (M=Pd, Pt) in MeCN under ambient conditions the ligands readily form complexes MLCl2 [6a–c (M=Pd), 7b (M=Pt)] via bidentate chelating coordination mode. The structures and stereochemistry both of the ligands and their complexes were confirmed by IR, multinuclear NMR and X-ray diffraction study. The palladium complexes demonstrated high activity as precatalysts for the Suzuki cross-coupling reaction, which was found to increase in the series 6a < 6b < 6c. [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: The formation of uranium complexes of novel ligands belonging to phosphorylated 2-oxo-1,2-azaphospholane series, namely 2-ethoxy-1-diethoxyphosphoryl-2-oxo-1,2λ5-azaphospholane (1a) and both individual R ∗,R ∗- and R ∗,S ∗-diastereomers of the related 2-oxo-2-phenyl-1,2λ5-azaphospholanes 1b,c with different surrounding at the exocyclic phosphorus atom, has been studied. The structures of the complexes of ML composition obtained in the reaction with uranyl nitrate in 1:1 ratio were found to depend on the difference in donor properties of the oxygen atom of endo- and exocyclic phosphoryl groups. The ligand 1a possessing the greater difference, serves as O-monodentate one with metal–oxygen bonding via the endocyclic Pn while both isomers of 1b,c coordinate to uranyl cation in a O,O-bidentate fashion. In solutions the ML complexes reacted with air oxygen to afford (μ2-peroxo)-bridged uranium complexes [{UO2(L)NO3}2(μ2-O2)] which structures were confirmed by X-ray crystallography data. [Copyright &y& Elsevier]