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Xumu Zhang - One of the best experts on this subject based on the ideXlab platform.
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rhodium catalyzed regioselective hydroaminomethylation of terminal olefins with pyrrole based Tetraphosphorus ligands
Catalysis Science & Technology, 2014Co-Authors: Huiling Geng, Guodu Liu, Xumu ZhangAbstract:A concise and elegant protocol was developed to prepare linear amines by regioselective hydroaminomethylation of terminal olefins with pyrrole-based Tetraphosphorus ligands. It has been documented that the reactivity of the ligand is modulated by the substituent of the biphenylphosphane moiety. Ligand L5 containing electron-donating groups exhibited the highest reactivity, with up to 70.9 n/i ratio and 99.5% amine selectivity for 1-pentene and a 31.3 n/i ratio and 97.9% amine selectivity for 1-hexene.
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rhodium catalyzed highly regioselective hydroaminomethylation of styrenes with Tetraphosphorus ligands
ChemInform, 2013Co-Authors: Kexuan Huang, Jiwen Zhang, Xumu ZhangAbstract:In contrast to other known methods the linear products are predominantly formed by this procedure.
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rhodium catalyzed highly regioselective hydroaminomethylation of styrenes with Tetraphosphorus ligands
Organic Letters, 2013Co-Authors: Kexuan Huang, Jiwen Zhang, Xumu ZhangAbstract:The highly linear-selective hydroaminomethylation of styrenes is very challenging. Herein, an efficient, highly chemoselective, and linear-selective hydroaminomethylation (l/b up to >99:1) of styrenes using Rh(nbd)2SbF6 with a pyrrole-based 3,3′,5,5′-substituted Tetraphosphorus ligand is documented. This is in sharp contrast to other available processes leading to branched amines and provides a novel atom economic approach to 3-arylpropylamines.
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New Tetraphosphorus Ligands for Highly Linear Selective Hydroformylation of Allyl and Vinyl Derivatives
Chemistry: A European Journal, 2012Co-Authors: Chaoxian Cai, Bonan Cao, Xumu ZhangAbstract:New Tetraphosphorus ligands have been developed and applied in the rhodium-catalyzed regioselective hydroformylation of a variety of functionalized allyl and vinyl derivatives. Remarkably high linear selectivity was obtained by these Tetraphosphorus ligands. The ligand that bears strong electron-withdrawing 2,4-difluorophenyl groups is the most effective one in affording linear aldehydes. The Rh/Tetraphosphorus ligand catalyst is highly effective to produce linear aldehydes from functionalized allyl derivatives with heteroatoms or aromatic groups directly adjacent to the allyl group. For vinyl derivatives, the ligand is highly linear selective for acrylic derivatives, styrene, vinyl pyridine, and vinyl phthalimide. Linear to branch ratios of 26:1 and 10:1 were obtained for the hydroformylation of styrene and allyl cyanide, respectively.
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highly regioselective hydroformylation of 1 5 hexadiene to linear dialdehyde catalyzed by rhodium complexes with Tetraphosphorus ligands
Tetrahedron Letters, 2009Co-Authors: Yuming Chie, Xiaowei Zhang, Liyan Dai, Xumu ZhangAbstract:Rhodium-catalyzed hydroformylation of 1,5-hexadiene to corresponding dialdehydes was investigated using Tetraphosphorus ligands. These ligands showed a high regioselectivity for linear aldehydes (linear to branch ratio up to 98%) in very good yield (up to 87%). It was found that the introduction of the substituents at the ortho position of the biphenyl moiety has little effect on the regioselectivity and the electron-donating substituents retard the reaction somewhat.
I S Nizamov - One of the best experts on this subject based on the ideXlab platform.
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optically active dithiophosphoric acid its ammonium salt and s esters on the basis of 1r endo fenchyl alcohol
Phosphorus Sulfur and Silicon and The Related Elements, 2014Co-Authors: G. T. Gabdullina, I S Nizamov, D. A. Terenzhev, Almaz R. Nurmukhametov, R A CherkasovAbstract:Optically active dithiophosphoric acid was prepared by the reaction of Tetraphosphorus decasulfide with (1R)-endo-(+)-fenchyl alcohol. The ammonium salt of dithiophosphoric acid prepared reacts wit...
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optically active s esters of dithiophosphoric acid on the basis of 1s endo borneol
Heteroatom Chemistry, 2013Co-Authors: I S Nizamov, G. T. Gabdullina, Almaz R. Nurmukhametov, R A CherkasovAbstract:The ammonium salt of optically active dithiophosphoric acid obtained by the reaction of Tetraphosphorus decasulfide with (1S)-endo-(–)-borneol reacts with benzoyl chloride, methyl chloroacetate and epichlorohydrin to form novel dithiophosphate S-esters.
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reactions of Tetraphosphorus decasulfide and lawesson s reagent with silanes containing a few si o bonds
Phosphorus Sulfur and Silicon and The Related Elements, 2000Co-Authors: I S Nizamov, E S Batyeva, A E Popovich, N M Azancheev, V A AlfonsovAbstract:Abstract The reactions of Tetraphosphorus decasulfide and Lawesson's reagent with tetra-, tri- and dialkoxysilanes were studied. On the basis of these reactions, new S-silyl esters of phosphorus(V) thioacids have been prepared. The prepared compounds were identified by IR, 1H, and 31P NMR and mass spectra as well as elemental analyses.
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dithiophosphoric acids and Tetraphosphorus decasulfide in the synthesis of boron dithiophosphates
Phosphorus Sulfur and Silicon and The Related Elements, 2000Co-Authors: I S Nizamov, G. G. Sergeenko, E S Batyeva, N M Azancheev, V A AlfonsovAbstract:Abstract The reactions of O,O-dialkyl dithiophosphoric acids with triisobutyl borate, ammonium O,O-diisobutyl dithiophosphate with fluorodiisobutyl borate, and Tetraphosphorus decasulfide with triisobutyl borate were studied. On the basis of these studies, new boron derivatives of dithiophosphoric acids were obtained. Low frequency ultrasonic irradiation (22 kHz, power 130 W) leads to reduction in reaction temperature and time in the reactions studied.
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new methods of syntheses of silyl derivatives of phosphorus v thioacids on the basis of Tetraphosphorus decasulfide 1 3 2 4 dithiadiphosphetane 2 4 disulfides and bis trimethylsilyl acetamide
Heteroatom Chemistry, 2000Co-Authors: I S Nizamov, E S Batyeva, A E Popovich, V A AlfonsovAbstract:Mixed O,S-bis- and tris(trimethylsilyl) esters of dithiophosphoric, aryldithiophosphonic and trithiophosphoric acids, 3, 7a–c, and 9, respectively, were obtained by the reactions of Tetraphosphorus decasulfide 1 and 1,3,2,4-dithiadiphosphetane-2,4-disulfides 6a–c and 8 with bis(trimethylsilyl)acetamide 2. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:276–280, 2000
Bruce W. Tattershall - One of the best experts on this subject based on the ideXlab platform.
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α Tetraphosphorus trichalcogenide diamides and imides containing both sulfur and selenium
Zeitschrift für anorganische und allgemeine Chemie, 2008Co-Authors: Bruce W. Tattershall, Kathryn E Holmes, Catherine Tweedy, Gina C ValksAbstract:Reaction of a mixture of bicyclic phosphorus sulfide selenide iodides α-P4SnSe3−nI2 (n = 0–3) with PriNH2 and Et3N gave corresponding diamides α-P4SnSe3−n(NHPri)2 (n = 0–3) and imides α-P4SnSe3−n(μ-NPri) (n = 2–3), identified in solution by 31P NMR. In one isomer of α-P4S2Se(μ-NPri), the C2 symmetry of imides such as α-P4S3(μ-NPri) was broken, allowing relative assignment of 2J NMR couplings to the PNP bridge and the PSP bridge opposite to it. The coupling through the sulfur bridge was found to be reduced to ca. zero, in contrast to previous assumptions for this class of compounds. Ab initio models were calculated at the MPW1PW91/svp level for the sulfide selenide imides and for a selection of bond rotamers of the diamides, and at the MPW1PW91/LanL2DZ(d) level for the sulfide selenide diiodides. Different skeletal isomers were prevalent for the mixed chalcogenide diamides than for the diiodides, showing that exchange of chalcogen between skeletal positions took place in the amination reaction even at room temperature. Similar differences to those observed were predicted by the models, suggesting that equilibrium was attained.
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sulfurisation of amino Tetraphosphorus trichalcogenide compounds
Zeitschrift für anorganische und allgemeine Chemie, 1996Co-Authors: Bruce W. Tattershall, Emma L SandhamAbstract:Amino Tetraphosphorus trisulfides α-P4S3(NR1R2)2 reacted with S8 under photolysis using visible light, in moderate or low conversion, to give α-P4S3(S)(NR1R2)2, in which the added sulfur atom was exocyclic. For NR1R2 = NPr2i, three isomers were found: a pair of diastereomers corresponding to attachment of the sulfur atom to a nitrogen-carrying phosphorus atom either with retention or with inversion of its configuration, and an isomer containing a sulfurised bridgehead phosphorus atom. For NR1R2 = NMePh, only the two diastereomers were seen. Photolysis of a mixture of α-P4Se3(NMePh)2 and α-P4Se3(NMePh)I with S8 gave as major products α-P4SSe2(NMePh)2 and α-P4SSe2(NMePh)I, in which sulfur had replaced the bridging selenium atom in the starting compounds. This provides a synthesis of compounds α-P4SSe2XY in which sulfur occupies a specific skeletal position, rather than being randomly distributed. All products were characterised by 31P NMR in unseparated solutions. Ab initio MO calculations of geometry and of GIAO NMR chemical shifts at the 3-21G* level for three isomers of the unknown model compound α-P4S3(S)(NH2)2, and two isomers of α-P4S3(NH2)2, allowed identification of the observed isomer of α-P4S3(S)(NPr2i)2 with a sulfurised bridgehead, but relative assignment of the two diastereomers to their NMR parameters remains a hypothesis. Sulfurisierung von Aminotetraphosphortrichalkogeniden Aminotetraphosphortrisulfide α-P4S3(NR1R2)2 reagieren mit S8 bei Bestrahlung mit sichtbarem Licht mit mittlerer oder geringerer Umsetzung der Ausgangsverbindung zu α-P4S3(S)(NR1R2)2, in denen das addierte Schwefelatom exostandig ist. Im Fall NR1R2 = NiPr2 wurden drei Isomere gefunden: ein Paar Diastereomere, die bei der Additionsreaktion des Schwefels an ein stickstofftragendes Phosphoratom moglicherweise unter Retention oder unter Inversion der Konfiguration gebildet wurden und ein Isomer, das ein sulfuriertes Bruckenkopf-Phosphoratom enthalt. Im Fall NR1R2 = NMePh wurden nur die beiden Diastereomere beobachtet. Bei der Photolyse einer Mischung von α-P4Se3(NMePh)2 und α-P4Se3(NMePh)I mit S8, entstanden α-P4SSe2(NMePh)2 und α-P4SSe2(NMePh)I als Hauptprodukte, in denen das jeweilige verbruckende Selenatom der Ausgangsverbindungen durch Schwefel ersetzt wurde. Dies ermoglicht die gezielte Synthese von Verbindungen des Typs α-P4SSe2XY, in denen Schwefel nur die Bruckenposition und nicht die anderen Chalkogenpositionen besetzt. Alle Produkte wurden ungetrennt in Losungen durch 31P NMR Spektroskopie charakterisiert. Ab initio MO Berechnungen der Geometrien und der GIAO NMR chemischen Verschiebungen, mit dem Basis-Satz 3-21G*, fur die drei Isomere der noch nicht synthetisierten Modellverbindung α-P4S3(S)(NH2)2 und fur die zwei Isomere von α-P4S3(NH2)2, ermoglichten die Identifikation des synthetisierten Isomers α-P4S3(S)(NiPr2)2 mit einem sulfurierten Bruckenkopf. Eine eindeutige Zuordnung der NMR-Parameter zu den beiden Diastereomeren ist noch nicht moglich.
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amino and μ imino Tetraphosphorus trisulfide compounds nmr evidence for invertomers and bridged cages with an α or β p4s3 skeleton
Polyhedron, 1996Co-Authors: R Blachnik, Kerstin Hackmann, Bruce W. TattershallAbstract:Abstract Reaction of α- or β -P 4 S 3 I 2 with RNH 2 (R = H, Me, Bu t or Ph) led to new iminobridged cage skeletons in α- or β -P 4 S 3 ( μ -NR), as well as both exo,exo - and endo,exo -isomers of either α- or β -P 4 S 3 (NHR) 2 (except for R = H). Cage compounds P 4 S 2 ( μ -NR) (R = Bu t or Ph) and α -P 4 S 2 ( μ -NR) 2 , with structures analogous to P 4 S 3 and α -P 4 S 4 , respectively, have been identified as decomposition products. The new compounds were characterised in solution by full analysis of their 31 P NMR spectra. The configuration at bridging nitrogen in α -P 4 S 3 ( μ -NR) was planar. An ab initio computation of molecular geometry of α -P 4 S 3 ( μ -NH) is reported. Mechanistic arguments are advanced to rationalise the formation of isomers endo,exo -α-P 4 S 3 (NHR) 2 , in contrast to corresponding reactions with secondary amines, which give only exo , exo - α -P 4 S 3 (NR 1 R 2 ) 2 .
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β Tetraphosphorus trichalcogenide compounds containing two different exocyclic ligands as well as both sulfur and selenium
Polyhedron, 1995Co-Authors: Bruce W. Tattershall, Roger Blachnik, Alexander HeppAbstract:Abstract All eight possible bicyclic molecules β-P4SnSe3−n(I)CHI2 (n = 0−3) were formed on reaction of mixtures of the tricyclic compounds P4SnSe3−n with CHI3 in solution in CS2, and identified in the reaction mixture by analysis of their 31P NMR spectra. Differences in coupling constants caused by the presence of sulfur rather than selenium in the products were interpreted in terms of concerted twisting of the fused five-membered rings, caused by a combination of the unsymmetric exocyclic ligand and endocyclic chalcogen substitution.
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phosphorus sulphide cage molecules with exocyclic phosphorus centred substituents nmr parameters for α Tetraphosphorus trisulphide compounds with pph2 p s ph2 or μ pph ligands
Polyhedron, 1994Co-Authors: Bruce W. Tattershall, Nigel L KendallAbstract:Abstract The symmetric compounds α-P4S3(PPh2)2 and α-P4S3[P(S)Ph2]2, and the two series of unsymmetric compounds α-P4S3(PPh2)R and α-P4S3[P(S)Ph2]R (R = I, NMePh or SPh), have been made in solution and studied by 31P NMR, allowing a comparison to be made of the effects of the PPh2 and P(S)Ph2 ligands on NMR coupling constants and chemical shifts. A statistical study of symmetric compounds α-P4S3R2 containing these ligands or 15 others showed that four out of six of the endocyclic NMR parameters of the α-P4S3 cage could be summarized by regression formulae involving two electronic and one steric substituent constants. Reaction of α-P4S3I2 with PhPH2 in the presence of Et3N gave the PPh-bridged molecule α-P4S3(μ-PPh).
Yuming Chie - One of the best experts on this subject based on the ideXlab platform.
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highly regioselective hydroformylation of 1 5 hexadiene to linear dialdehyde catalyzed by rhodium complexes with Tetraphosphorus ligands
Tetrahedron Letters, 2009Co-Authors: Yuming Chie, Xiaowei Zhang, Liyan Dai, Xumu ZhangAbstract:Rhodium-catalyzed hydroformylation of 1,5-hexadiene to corresponding dialdehydes was investigated using Tetraphosphorus ligands. These ligands showed a high regioselectivity for linear aldehydes (linear to branch ratio up to 98%) in very good yield (up to 87%). It was found that the introduction of the substituents at the ortho position of the biphenyl moiety has little effect on the regioselectivity and the electron-donating substituents retard the reaction somewhat.
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highly regioselective and rapid hydroformylation of alkyl acrylates catalyzed by a rhodium complex with a Tetraphosphorus ligand
Advanced Synthesis & Catalysis, 2009Co-Authors: Yuming Chie, Xumu ZhangAbstract:Alkyl acrylates have been hydroformylated to the linear aldehydes with high regioselectivity (linear/branch > 99/1) and extraordinarily high average turnover frequencies (up to 5400 h -1 ) by using a rhodium complex with a Tetraphosphorus ligand. This protocol is in sharp contrast to the most of other processes that favor production of the branched aldehyde (typically > 95% branched for most Rh-catalyzed reaction systems). The high turnover number achieved by this new catalytic system is also remarkable considering the less reactive character of alkyl acrylates to the hydroformylation reaction conditions.
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highly regioselective hydroformylation of styrene and its derivatives catalyzed by rh complex with Tetraphosphorus ligands
Organic Letters, 2009Co-Authors: Yuming Chie, Zhenghui Guan, Yaping Zou, Xumu ZhangAbstract:Styrene has been hydroformylated to the linear aldehyde with surprisingly high regioselectivity (l/b up to 22 for styrene) by using Rh complex with Tetraphosphorus ligand. To the best of our knowledge, this is the highest linear regioselectivity reported for the hydroformylation of styrene and its derivatives. This protocol is in sharp contrast to other processes that favor producing branched aldehyde (typically >95% branched for most bidentate systems).
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highly regioselective isomerization hydroformylation of internal olefins to linear aldehyde using rh complexes with Tetraphosphorus ligands
Organic Letters, 2008Co-Authors: Yuming Chie, Zhenghui Guan, Xumu ZhangAbstract:A series of new pyrrole-based Tetraphosphorus ligands were synthesized and used for Rh-catalyzed isomerization−hydroformylation of internal olefins. It was found that the substituents at the 3,3′,5...
Cherkasov R. - One of the best experts on this subject based on the ideXlab platform.
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Optically active dithiophosphoric acid, its ammonium salt, and S-esters on the basis of (1 R)-endo-(+)-fenchyl alcohol
2020Co-Authors: Gabdullina G., Terenzhev D., Nurmukhametov A., Cherkasov R.Abstract:© 2014 Taylor and Francis Group, LLC. Optically active dithiophosphoric acid was prepared by the reaction of Tetraphosphorus decasulfide with (1R)-endo-(+)-fenchyl alcohol. The ammonium salt of dithiophosphoric acid prepared reacts with methyl chloroacetate and benzoyl chloride to give dithiophosphate S-esters
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Optically active s-esters of dithiophosphoric acid on the basis of (1S)-endo-(-)-borneol
2020Co-Authors: Gabdullina G., Nurmukhametov A., Cherkasov R.Abstract:The ammonium salt of optically active dithiophosphoric acid obtained by the reaction of Tetraphosphorus decasulfide with (1S)-endo-(-)-borneol reacts with benzoyl chloride, methyl chloroacetate and epichlorohydrin to form novel dithiophosphate S-esters. © 2013 Wiley Periodicals, Inc
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Dithiophosphoric and dithiophosphonic acids and their derivatives on the basis of thymol: Synthesis and antimicrobial activity
2020Co-Authors: Cherkasov R., Gabdullina G., Almetkina L., Shamilov R., Sofronov A.Abstract:Biologically active dithiophosphoric and dithiophosphonic acids, their ammonium salts as well as S-silyl and S-plumbyl derivatives were prepared by the reaction of thymol with Tetraphosphorus decasulfide and 2,4-diaryl 1,3,2,4-dithiadiphosphetane-2,4-disulfides. © 2013 Copyright Taylor and Francis Group, LLC
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New phosphorus dithioacids and their derivatives containing chiral centers and pharmacophoric groups
2020Co-Authors: Terenzhev D., Sabirzyanova G., Salikhov R., Cherkasov R.Abstract:© 2016 Taylor & Francis Group, LLC.New phosphorus dithioacids, their ammonium salts and S-silyl and plumbyl derivatives containing asymmetric carbon atoms and pharmacophoric groupswere obtained by the reactions of Tetraphosphorus decasulfide and 1,3,2,4-dithiadiphosphetane-2,4-disulfides with chiral natural terpenyl alcohols, diols, carboxylic acid esters, amino acids and monosaccharides as well as synthetic chiral amines and 1-phenylethanol. The biological activity of the ammonium salts and S-esters of phosphorus dithioacids were studied
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Cinchona Alkaloids in the Synthesis of Chiral Salts of Phosphorus Dithioacids on the Basis of 1,2:3,4-Di-O-isopropylidene-α-D-galactopyranose
2020Co-Authors: Shumatbaev G., Salikhov R., Nikitin Y., Shulaeva M., Pozdeev O., Batyeva E., Cherkasov R.Abstract:© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Optically active dithiophosphoric and dithiophosphonic acids were obtained by the reactions of 1,2:3,4-di-O-isopropylidene-α-D-galactopyranose with Tetraphosphorus decasulfide or Lawesson's reagent respectively. The reactions of dithiophosphoric and dithiophosphonic acids with 8 S,9R-quinine, 8R,9 S-quinidine, 8 S,9R-cinchonidine, 8R,9 S-cinchonine, and 8R,9 S-hydroquinidine result in chiral salts of dithiophosphoric and dithiophosphonic acids. Antimicrobial activity of products obtained was tested
