Alexander V. Artem'ev

Superbase-Assisted Addition of Phosphine to 1-Methoxy-4-vinylbenzene: Toward a Rare Family of Organic Phosphines

Abstract Phosphine reacts with 1-methoxy-4-vinylbenzene in the superbase suspension KOH-dimethylsulfoxide (70–100 °C, atmospheric pressure) to form regiospecifically anti-Markovnikov adducts, bis[2-(4-methoxyphenyl)ethyl]phosphine (1) and tris[2-(4-methoxyphenyl)ethyl]phosphine (2), representatives of rare arylalkylphosphines. The conditions for the selective preparation of phosphines 1 or 2 in 67% and 80% yields, respectively, have been elaborated. The phosphines have been oxidized with aqueous solution of H2O2, elemental sulfur, or selenium to afford the corresponding phosphine chalcogenides in good yields (95–99%). GRAPHICAL ABSTRACT

Novel atom-economic synthesis of thioselenophosphinates via three-component reaction between secondary phosphine sulfides, elemental selenium, and amines

An efficient, general, and atom-economic synthesis of organoammonium thioselenophosphinates has been developed by exploiting a three-component reaction between secondary phosphine sulfides, elemental selenium, and various amines. The reaction proceeds under mild conditions (70–75 °C, 1 h, EtOH) to afford thioselenophosphinates in 77–94% yields.

One-pot atom-economic synthesis of Se-[alkyl(aryl)sulfanylethyl]diselenophosphinates from vinyl sulfides, secondary phosphines and elemental selenium

Alkyl(or aryl)vinyl sulfides react chemo- and regioselectively with secondary phosphines and elemental selenium (1.1:1:2 molar ratio) at 100°C (1,4-dioxane, 1.5 h) to form functionalized Se-[1-(organosulfanyl)ethyl]diselenophosphinates in 83–94% yields.

Electrophilic addition of thioselenophosphinic acids to vinyl sulfides and selenides

The thioselenophosphinic acids, R2P(Se)SH (R = Ph, Cy, aralkyl), prepared by acidification of the sodium salts or generated in situ by reaction of secondary phosphine sulfides with elemental selenium, add easily to diverse vinyl sulfides and vinyl selenides in a Markovnikov manner to give the corresponding S- and Se-esters in a ∼60:40 molar ratio (83–96% total yield). GRAPHICAL ABSTRACT

Atom-economic synthesis of highly branched functional ‘tripod-like’ triphosphine sulfides

The tertiary polyfunctional triphosphine sulfides with amino and (or) ether groups have been synthesized in excellent yields by the exhaustive regioselective (in anti-Markovnikov manner) addition of secondary phosphines sulfides to trivinyl ethers of aminotriols and triols under free-radical conditions (UV-irradiation, 1.5–5 h). GRAPHICAL ABSTRACT

Three-component reaction between elemental sulfur, primary phosphines, and amines: straightforward synthesis of organylammonium trithiophosphonates

Elemental sulfur reacts with primary phosphines and various amines in the 3:1:2 molar ratio under mild conditions (60°C, 10 min, ethanol) to afford hitherto unknown organylammonium trithiophosphonates in 84–91% yields.

Hemilability of phosphine-thioether ligands coordinated to trinuclear Mo3S4 clusters and its effect on hydrogenation catalysis

Ligand-exchange reactions of [Mo3S4(tu)8(H2O)]Cl4·4H2O (tu = thiourea) with (PhCH2CH2)2PCH2CH2SR ligands, where R = Ph (PS1), pentyl (PS2) or Pr (PS3), afford new complexes isolated as [Mo3S4Cl3(PS1)3]PF6 ([1]PF6), [Mo3S4Cl3(PS2)3]PF6 ([2]PF6) and [Mo3S4Cl3(PS3)3]PF6 ([3]PF6) salts in 30–50% yields as the major reaction products. The crystal structures of [1]PF6 and [2]PF6 were determined by X-ray diffraction (XRD) analysis. Each of the three phosphine-thioether ligands is coordinated in a bidentate chelating mode to a different molybdenum atom of the Mo3S4 trinuclear cluster; herein, all the phosphorus atoms of the phosphino-thioether ligand are located trans to the capping sulfur (μ3-S). A second product that forms in the reaction of [Mo3S4(tu)8(H2O)]Cl4·4H2O with PS1 corresponds to the neutral [Mo3S4Cl4(PS1)2(PS1*)] complex. Its XRD analysis reveals both bidentate (PS1) and monodentate (PS1*) coordinating modes of the same ligand. In the latter mode the phosphine-thioether is coordinated to a Mo atom only via the P atom. All compounds were characterized using 1H and 31P{1H} NMR spectroscopy, electrospray-ionization (ESI) mass spectrometry and cyclic voltammetry (CV). Reactions of [1]PF6, [2]PF6 and [3]PF6 with an excess of Bu4NCl in CD2Cl2 were followed by 31P{1H} NMR spectroscopy. The spectra indicate equilibrium between cationic [Mo3S4Cl3(PSn)3]+ and neutral [Mo3S4Cl4(PSn)2(PSn*)] (n = 1, 2) species. The equilibrium constants were determined as 2.5 ± 0.2 × 103 M−1, 43 ± 2 M−1 and 30 ± 2 M−1 (at 25 °C) for [1]PF6, [2]PF6 and [3]PF6, respectively, indicating quantitative differences in the hemilabile behaviors of the phosphino-thioether ligands, depending on the substituent at the sulfur. Clusters [1]PF6, [2]PF6 and [3]PF6 were tested as catalysts in the reduction of nitrobenzene to aniline with Ph2SiH2 under mild conditions. Significant differences in the catalytic activities were observed, which can be attributed to different hemilabile behaviors of the PS1 and PS2/PS3 ligands.