The in situ generation of Ph3P=C(CF3)2. a facile one pot conversion of aldehydes to bis-trifluoromethyl olefins.

The in situ reaction of triphenylphosphine with tetrakis(trifluoromethyl)-1,3-dithietane in the presence of aliphatic or aromatic aldehydes gives good to excellent yields of bis-trifluoromethyl olefins.     

Kinetics and mechanism of styrene hydroalkoxycarbonylation catalyzed by the complex PdCl2(Ph3P)2 in the presence of butanol

The single-factor experiment method was used to study the kinetics of styrene hydrobutoxycarbonylation catalyzed by the complex PdG₂(Ph₃P)₂ in dioxane (383 K, [BuOH] = 1–8 mol/1). The rates of accumulation of the regioisomeric reaction products as empirical functions of CO pressure and concentrations of styrene, triphenylphosphine, and the catalyst were found. The acyl complex (PhC₂H₄CO)PdCl(Ph₃P)₂ was isolated from the reaction mixture. The assumed intermediate of an alcoholate mechanism, the (BuOOC)PdCl(Ph₃P)₂ complex, is not formed by the reaction of PdCl₂(Ph₃P)₂ with CO and butanol. The set of data generally corresponds to a hydride mechanism of styrene hydrocarboxylation, which includes three key intermediates HPdCIL_2-n(CO)_n (n= 0–2). A change in the solvation properties of the reaction medium due to the replacement of water by butanol affects the kinetic scheme of the process.     

One‐Pot Synthesis of Tetraalkyl Benzene‐1,2,3,5‐tetracarboxylates from a Four‐Component Reaction of Alkyl Propiolates and Alkyl 2‐Nitroethanoates Promoted by Ph3P

Alkyl 2‐nitroethanoates react with alkyl propiolates in the presence of triphenylphosphine (Ph₃P) in a mechanistically unprecedented reaction to afford tetraalkyl benzene‐1,2,3,5‐tetracarboxylates in moderate yields (36–42%).     

三苯基磷对PTG材料照相性能的影响

本文研究了三苯基磷(PPh₃)对以AgSt为银源的亲水型PTG材料照相性能的影响:PTG材料的感光度随PPh₃用量不同而变化,PPh₃用量相对较少时,感光度随PPh₃用量增加而提高;PPh₃用量增加到一定程度,感光度达到极大值;进一步增加PPh₃用量,感光度反而随PPh₃用量增加而下降.据分析结果推测,在PPh₃用量较少时,PPh₃的作用主要是打开AgSt二聚体的八元环而生成一种中间配合物,该中间体对热显影有促进作用;在PPh₃用量较多时,PPh₃的作用主要是与AgSt作用生成稳定的四元环配合物,该配合物对热显影有抑制作用.PPh₃的引入也会影响光敏元中潜影的形成效率,有利于提高感光度.     

A coordination polymer of (Ph3P)AuCl prepared by post-synthetic modification and its application in 1-hexene/n-hexane separation

PCM-10 is a porous phosphine coordination material based on Ca(II) and tris(p-carboxylated) triphenylphosphine. The material provides a unique 3-dimensional surface of P(III) Lewis base sites, which is ideal for post-synthetic functionalization. The addition of Au(I) yields an advanced material that can selectively adsorb 1-hexene over n-hexane at room temperature.     

Synthesis of Aryl α,α-Difluoroalkyl Ketones as Potent Inhibitors of Cholesterol Esterase

Aryl α,α-difluoroalkyl ketones were synthesized from the reaction of ethyl α,α-difluoroacylate with aryl lithium at ?78°C or from the coupling of aryl iododifluoromethyl ketone with 1-alkene in the presence of tetcrakis(triphenylphosphine)palladium(0). These compounds were potent inhibitors of pancreatic cholesterol esterase with K_i values in the range 15 μM-20 nM.     

Computational study of sulfur atom-transfer reactions from thiiranes to ER3 (E = As, P; R = CH3, Ph)

Computational estimates have been made for the P=S and As=S bond strengths in triphenylphosphine sulfide and triphenylarsine sulfide, on the basis of G3 calculations for the methyl analogues and isodesmic-exchange reactions. Also, with the performance of the G3 method level for related compounds taken into consideration, the best estimates are 82 and 68 kcal/mol, respectively. While the value for triphenylarsine sulfide is within 2 kcal/mol of the single experimental estimate, that for triphenylphosphine sulfide is lower by 6 kcal/mol. (Capps, K. B.; Wixmerten, B.; Bauer, A.; Hoff, C. D. Inorg. Chem. 1998, 37, 2861-2864.) Despite virtually identical electronegativities of P and As, it is found that there is greater charge separation in the P=S bond. It is found that S atom transfer from thiiranes to arsines is exothermic.     

EPR Studies of (3, 5-di-t-Butyl-0-Benzoquinone) Tetracarbonylrhenium(0) Radical

The organometallic radical: (3,5-di-t-butyl-0-benzoquinone)tetracarbonyl-rhenium(0) and its triphenylphosphine substituted derivatives were studied by EPR spectroscopy. The unpaired electron is shown to be localized in the organic 1,2-diketone ligand. The rate of carbonyl substitution by triphenylphosphine at the unsubstituted rhenium radical indicates a second order reaction. The activation parameters are ΔH* =19.1±0.8Kcal/mole and ΔS*-3.0±1.5 eu/mole.     

Methyl-perthiooxalate und deren Reaktion mit Ph3P

Methyl-perthiooxalates and their Reaction with Ph₃ O-Methyl-1,1-dithiooxalate reacts with d⁸ transition metal ions with the spontaneous formation of mononuclear perthio/dithiooxalate complexes [(i-dtoMe)M(ptoMe)] (M = Ni, Pd, Pt). The mass spectrometric fragmentation of this complexes is discussed. The spontaneous sulfur insertion can be reversed by reaction with Ph₃P. Following up reactions with different Ph₃P equivalents are investigated for the Ni^II compound. Beside the synthesis of the square planar mixed ligand complex [(Ph₃P)Ni(i-dtoMe)₂] a Ni^I complex was detected by EPR spectroscopy.     

Facile synthesis of highly functionalized six-membered heterocycles via PPh3-catalyzed [4+2] annulations of activated terminal alkynes and hetero-dienes: scope, mechanism, and application

A novel [4+2] annulation between activated terminal alkynes and aza-dienes or oxo-dienes has been developed with the use of triphenylphosphine catalyst (20 mol %), which provides a facile method for synthesis of the corresponding highly functionalized dihydropyridines or dihydropyrans in good to excellent yields. The reaction mechanism has also been established, consisting formal hetero-Diels-Alder reaction catalyzed by PPh₃ and [1,3]-proton transfer, which exhibits a large isotopic effect.     

Solvent-free mechanochemical synthesis of two Pt complexes: cis-(Ph3P)2PtCl2 and cis-(Ph3P)2PtCO3

Cis-(Ph3P)2PtCl2 and cis-(Ph3P)2PtCO3 were prepared mechanochemically from solid reactants in the absence of a solvent; cis-(Ph3P)2PtCl2 was obtained in 98% yield after ball-milling of polycrystalline PtCl2 and Ph3P; the mechanically induced solid-state reaction of cis-(Ph3P)2PtCl2 with an excess of anhydrous K2CO3 produced cis-(Ph3P)2PtCO3 in 70% yield; the formation of transition metal complexes as a result of mechanochemical solvent-free reactions has been confirmed by means of solid-state 31P MAS NMR spectroscopy, X-ray powder diffraction and differential thermal analysis.     

The conversion of 2-(4-chloro-5H-1,2,3-dithiazolylideneamino)benzonitriles into 3-aminoindole-2-carbonitriles using triphenylphosphine

2-(4-Chloro-5H-1,2,3-dithiazolylideneamino)benzonitrile 1a reacts with triphenylphosphine (4 equiv) in the presence of water (2 equiv) to afford anthranilonitrile 2a, 3-aminoindole-2-carbonitrile 3a and (2-cyanoindol-3-yl)iminotriphenylphosphorane 4a, together with triphenylphosphine sulfide and oxide. The use of polymer bound triphenylphosphine provides cleaner reaction mixtures. 2-(4-Chloro-5H-1,2,3-dithiazolylideneamino)-4,5-dimethoxybenzonitrile 1h does not give the corresponding indole on treatment with triphenylphosphine but gives 6,7-dimethoxyquinazoline-2-carbonitrile 5 (15%) and 2-cyano-4,5-dimethoxy cyanothioformanilide 6 (36%). A total of seven new 3-aminoindole-2-carbonitriles 3a-g are prepared and fully characterised.     

Ph2P(BH3)Li: from ditopicity to dual reactivity

A multinuclear NMR study shows that the deprotonation of diphenylphosphine-borane by n-BuLi in THF leads to a disolvated lithium phosphido-borane Ph(2)P(BH(3))Li of which Li(+) is connected to the hydrides on the boron and two THF molecules rather than to the phosphorus. This entity behaves as both a phosphination and a reducing agent, depending on the kinetic or thermodynamic control imposed to the reaction medium. Density functional theory computations show that H(2)P(BH(3))Li exhibits a ditopic character (the lithium cation can be in the vicinity of the hydride or of the phosphorus). It explains its dual reactivity (H- or P-addition), both routes going through somewhat similar six-membered transition states with low activation barriers.     

三苯基膦亚铜配合物光解反应的ESR研究

用自旋捕捉技术-柱色谱-电子自旋共振相结合的方法研究了(Ph3)3CunXn(n=1,2; x=Cl,Br,I,CN)和(Ph3P)(biL)CuX(X=Cl,Br,I;biL-2,2'-二吡啶基-1,10-菲绕啉光解中的活性自由基.通过在苯基自由基,二苯基膦自由基与苯基丁基氧化氮之间生成的自旋加合物的电子顺磁共振谱的超精细结构,证实了苯基自由基和二苯基膦自由基的生成.标题化合物对某些反应具有催化活性.     

STUDIES ON SUBSTITUTION OF C=O IN BIS(μ-ALKYLTHIO)-HEXACARBONYLDI-IRONS----THE SYNTHESIS AND STRUCTURES OF(μ-RS)(μ-R'S)Fe2(CO)5Ph3

Fourteen new PPh3 substituted Fe-S clusters,with general formula (μ-RS)(μ-R'S)Fe2(CO)5 PPh3,have been synthesized by reaction of unsymmetrical type of bis(μ-alkylthio ) hexacarbonyldiirons with triphenylphosphine.Based on the discussion of influence of PPh3 on VCO and alkyl spacial orientation of PPh3 in clusters has also been established.     

High-pressure vibrational study of the catalyst candidate cis-dimercaptobis(triphenylphosphine)platinum(II), cis-[(Ph3P)2Pt(SH)2

Infrared and FT-Raman spectra of cis-dimercaptobis(triphenylphosphine)platinum(II), cis-[(PPh3)2Pt(SH)2], have been measured at high external pressures up to 55 kbar with the aid of a diamond-anvil cell (DAC). The wavenumber (v) versus pressure (P) plots from the Raman data indicate the occurrence of a pressure-induced phase transition at around 15 kbar. The metal-ligand stretching mode, v(Pt-S), and the C-H stretching mode of the phenyl rings, v(C-H), are highly sensitive to the application of pressure (dv/dP approximately 1.0 cm(-1) kbar(-1)). The IR results are generally consistent with the Raman data. The pressure-induced phase transition is most probably attributable to the reorientation of the phenyl rings in the complex; similar results have been obtained for other phenyl derivatives.     

PdCl2-NiCl2-PPh3/PVP催化苯乙烯高区域选择性的氢酯化反应

烯烃与CO和醇的催化氢酯化反应是合成竣酸酯的一种简便方法．当烯烃是芳香烯烃时,其产物可用来制备极有价值的非自类解热镇痛抗炎药物ibaprofe。。、naproxen（支链型2一芳基丙酸类）：ArCH。（二。＋CO＋ROH、ArCH（CH。）COOR＋ArCH。CH。COOR＋ArCHfH。toRPd（OAc）。－rnontmorlllonlte－PPh。－HC卜和Pd（OAc）。－PPh。－p－toluenesulfonicacid'惮金属体系在高PPh。／Pd比的PPhs存在下,可高转化率、高选择性地催化芳香烯烃氢酯化反应生成支链酯．近年来高分子负载的双金属体系在选择性加氢"'、加氢脱氯"'中表…     

Cyclometalated Arylazo Compounds. Part 4. ortho-cyano-1-arylazonaphthalenes and 3-amino-2-arylbenzo [g]indazoles from cyclopalladated 1-arylazonaphthalenes. 4th communication on compounds with a metal-arene σ-bond

The reaction of a cyclopalladated 1-arylazonaphthalene with tetrabutylammonium cyanide leads to an ortho-cyano-1-arylazonaphthalene and a 3-amino-aryl-benzo[g]indazole, depending upon whether triphenylphosphine or 1,2-bis(diphenyl-phosphino)ethane (DIPHOS) is used to monomerize the binuclear Pd(II)-complex. In a similar insertion reaction with cyclohexyl isocyanide the corresponding 3-(N-cyclohexyl)-aminoindazole is formed. A Pd(II)-isocyano complex is shown to be a possible intermediate in that conversion.     

Trifluoromethylation of Propargylic Halides and Trifluoroacetates Using (Ph(3)P)(3)Cu(CF(3)) Reagent

A copper-mediated trifluoromethylation of propargylic halides and trifluoroacetates was performed with high allenyl or propargyl selectivity. The reaction proceeds smoothly with aliphatic and aromatic substituents bearing either electron-withdrawing or -supplying groups. Preliminary mechanistic results indicate an ionic mechanism involving nucleophilic transfer of the CF(3) group from the Cu complex to the propargylic substrate.     

Reaction of N-sulfinyltrifluoromethanesulfonamide with triphenylphosphine and triphenylphosphine oxide

The reaction of N-sulfinyltrifluoromethanesulfonamide with triphenylphosphine and triphenylphosphine oxide or of trifluoromethanesulfonamide with dichloro(triphenyl)phosphorane leads to trifluoro-N-(triphenyl-λ⁵-phosphanylidene)methanesulfonamide, which is hydrolyzed to trifluoromethanesulfonamide and triphenylphosphine oxide via the intermediate trifluoro-N-[hydroxy(triphenyl)phosphoranyl]methanesulfonamide.