111-71-7Relevant articles and documents
Preparation and catalytic properties of resin bound binuclear rhodium tetracarboxylate complexes
Andersen, Jo-Ann M.,Karodia, Nazira,Miller, David J.,Stones, Duane,Gani, David
, p. 7815 - 7818 (1998)
4-(4'-Polystyryimethyloxy)-3-carboxylatomethyloxy-1-phenylacetate bis- μ-coordinated rhodium(II) diacetate complex, a resin-bound analogue of dirhodium tetraacetate in which two adjacent μ-bridging acetate moleties are covalently linked, serves as an efficient, stable and re-useable immobilised alkene hydrofomylation and hydrogenation catalyst.
Low pressure catalytic hydroformylation of 1-hexene by the carbonylhydrido-tris(triphenylphosphine)rhodium(I), RhH(CO)(PPh3)3, in association with phosphinomethylzirconium complexes
Choukroun, R.,Gervais, D.,Kalck, P.,Senocq, F.
, p. C9 - C12 (1987)
Low pressure catalytic hydroformylation of 1-hexene was performed in the presence of RhH(CO)(PPh3)3 in association with diphenylphosphinomethylzirconium complexes such as Cp2Zr(CH2PPh2)2 and 2O or in the presence of bis(diphenylphosphine)butane.An isolated rhodium-zirconium complex, formulated as , was found to be catalytically active.
Sulphur-containing Dinuclear Rhodium Complexes as Catalyst Precursors for the Selective Hydroformylation of Alkenes
Kalck, Philippe,Frances, Jean-Marc,Pfister, Pierre-Marie,Southern, Timothy G.,Thorez, Alain
, p. 510 - 511 (1983)
Dinuclear thiolato bridged complexes, particularly 2>, catalyse the hydroformylation of hex-1-ene at low pressure and temperature to afford selectively and with high turnover rates the corresponding aldehydes.
Study of reaction and kinetics in pyrolysis of methyl ricinoleate
Guobin, Han,Zuyu, Liu,Suling, Yao,Rufeng, Yan
, p. 1109 - 1112 (1996)
The effects of pyrolysis temperature, space-velocity, and dilution ratio of starting materials on the reaction have been studied in the pyrolysis of methyl ricinoleate. The reaction parameters were optimized to obtain yield ranges of 25.8-26.7% for heptaldehyde and 45.7-46.5% for methyl undecenoate. The kinetic study showed that pyrolysis of methyl ricinoleate is a first-order reaction at 828-878 K, and the activation energy is 1.729 × 105 J/mol.
Hydroformylation in perfluorinated solvents; improved selectivity, catalyst retention and product separation
Foster, Douglas F,Gudmunsen, David,Adams, Dave J,Stuart, Alison M,Hope, Eric G,Cole-Hamilton, David J,Schwarz, Gary P,Pogorzelec, Peter
, p. 3901 - 3910 (2002)
The hydroformylation of linear terminal alkenes using rhodium based catalysts under fluorous biphasic conditions in the presence and absence of toluene is reported. Using fluorinated ponytails to modify triarylphosphites and triarylphosphines, good selectivities and reactivities can be obtained, along with good retention of the catalyst and ligand within the fluorous phase. Using P(O-4-C6H4C6F13)3 (P/Rh=3:1) as the ligand in toluene/perfluoro-1,3-dimethylcyclohexane, good results are obtained at 60°C, but decomposition of the catalyst and/or ligand occurs on increasing the temperature. More impressive results are obtained by omitting the toluene, with higher rates, better l/b ratios, and better retention of the catalyst and the phosphite within the perfluorocarbon solvent. Competing isomerisation restricts linear aldehyde selectivities to 6H4C6F13)3 is used as the ligand in the absence of toluene, even more impressive results can be obtained, with linear aldehyde selectivities up to 80.9%, high rates, and the retention of up to 99.95% of the rhodium and up to 96.7% of the phosphine within the fluorous phase. These results are compared with those of commercial systems for propene hydroformylation and with those previously reported in the literature for hydroformylation under fluorous biphasic conditions. Phase behaviour studies show that 1-octene is completely miscible with the fluorous solvent under the conditions used for the hydroformylation experiments, but that the product nonanal, phase separates.
Selective Hydroformylation with a Recoverable Dirhodium μ-Thiolato Complex
Bayon, J. C.,Real, J.,Claver, C.,Polo, A.,Ruiz, A.
, p. 1056 - 1057 (1989)
The dimeric precursor complex 2(cod)2>, (cod=cyclo-octa-1,5-diene), with PPh3 catalyses the hydroformylation of hex-1-ene, under mild conditions, into heptanals with high yields and selectivities; owing to the presence of the amine group the rhodium catalyst can be quantitatively recovered from the reaction mixture by adding dilute H2SO4, and reused without loss of activity.
Hydroformylation of olefins catalysed with bimetallic systems: HRh{P(OPh) 3}4 + cp2ZrH(CH2PPh2) and HRh(CO) {P(OPh) 3}3 + cp2ZrH(CH2PPh2)
Trzeciak, Anna M.,Ziotkowski, Jozef J.,Choukroun, Robert
, p. 145 - 149 (1996)
The catalytic activity of bimetallic systems containing the rhodium complex HRh{P(OPh)3}4 or HRh(CO){P(OPh)3}3 and the Zr(IV) complex cp2ZrH(CH2PPh2) was tested in the hydroformylation reaction of 1-hexene and E-,Z-2-hexene. An increase in n/iso ratio (from 2.2 to 3.5 in the case of HRh{P(OPh)3}4 and from 0.4 to 3.7 in the case of HRh(CO){P(OPh)3}3) was observed in 1-hexene hydroformylation in the presence of cp2ZrH(CH2PPh2).
Manninen,Krieger
, p. 2071 (1967)
Describing the Reaction of the Hydrocarboxylation of 1-Hexene, Catalyzed by Co2(CO)8, in Marcelin–de Donde Kinetics
Vigranenko, Yu. T.,de Vekki,Krylova,Koluzhnikova
, (2020)
Abstract: An equation is derived for calculating the rate coefficient of the 1-hexene hydrocarboxylation reaction in Marcelin–de Donde kinetics. The equation correctly describes experimental data in the range of concentrations of an unsaturated substrate,
Biphase hydroformylation catalyzed by rhodium in combination with a water-soluble pyridyl-triazole ligand
Scrivanti, Alberto,Beghetto, Valentina,Alam, Md. Mahbubul,Paganelli, Stefano,Canton, Patrizia,Bertoldini, Matteo,Amadio, Emanuele
, p. 613 - 617 (2017)
[RhCl(COD)]2in combination with a water soluble sulphonated pyridyl-triazolyl N,N-bidentate ligand efficiently catalyzes styrene and 1-hexene hydroformylation in water/organic solvent biphasic systems. The catalyst displays a good activity affording mixtures of linear and branched aldehydes with complete chemoselectivity. The aqueous catalytic phase may be recycled four times giving complete substrate conversion by 18 h. Mercury-poisoning experiments and transmission electron microscopy indicate that, after the first catalytic run, rhodium is present in the aqueous phase in nanoparticle form.
THE SYNTHESIS OF PGF1α BY RE-STRUCTURING OF CASTOR OIL
Ranganathan, D.,Ranganathan, S.,Mehrotra, M. M.
, p. 1869 - 1876 (1980)
Castor oil has been transformed - via methyl ricinoleate - to PGF1α by strategy wherein 16 of the 18 carbons of the castor oil backbone are incorporated in the C-20 PGF1α, involving, inter alia, a novel procedure for the regiospecific functionalisation of terminal olefins, a novel degradation of aldehyde to lower acid and strategies useful for the generation of the highly functionalised prostanoid system, which specially illustrate the utility of MEM protecting group in diverse types of chemical transformations.Additionally, this work describes the preparation of synthons having potential utility and the synthesis of novel homo-PGF1α.
New glycosphingolipids from the fungus Catathelasma ventricosa
Zhan, Zha-Jun,Yue, Jian-Min
, p. 1013 - 1016 (2003)
Three new glycosphingolipids with a cis-Δ17-fatty acyl moiety, namely, catacerebrosides A-C (1-3), along with two known glycosphingolipids, cerebrosides B and D, six known ergostane-type sterols, and tyrosamine were isolated from the fungus Catathelasma ventricosa. The structures of 1-3 were elucidated on the basis of spectroscopic analysis and chemical methods.
Impact of structured catalysts in amine oxidation under mild conditions
Santos, Jose Luis,Navarro, Pablo,Odriozola, Jose Antonio,Centeno, Miguel Angel,Pavel, Octavian D.,Jurca, Bogdan,Parvulescu, Vasile I.
, p. 266 - 272 (2016)
A structured graphene/graphite catalyst grown on a commercial austenitic stainless steel sheet providing a micromonolith was obtained by submitting the nude stainless steel structure to a carbon-rich atmosphere (first 300 mL/min of a reductive H2/N2 (1:1) flow, then to 180 mL/min of a CH4/H2 (1:5)) at high temperature (900 °C) for 2 h. The preparation procedure resulted in a homogenous surface coated with a carbon-rich film as observed by EDX and SEM images. Further characterizations by Raman spectroscopy revealed characteristic Raman lines of graphene and crystalline graphite disposed in a hierarchical organization. The disposal of the obtained surface layers was also confirmed by grazing incidence X-ray diffraction. Besides this, XRD indicated the overlapping diffraction lines of graphite, cementite and M7C3 carbides. The graphene nature of the outermost layer was also confirmed by XPS. The catalytic behavior of the structured graphene/graphite catalyst was evaluated in the selective oxidation of heptylamine. At 200 °C it afforded a total conversion with a combined selectivity in heptanonitrile and N-heptylidene-heptylamine of 67% (10% heptanonitrile) that corresponds indeed to a very efficient system in the absence of any metal. Kinetic experiments with the scope to calculate the activation energies were also performed.
MCM-41 supported water-soluble TPPTS-Rh complex in ionic liquids: A new robust catalyst for olefin hydroformylation
Yang, Yong,Lin, Haiqiang,Deng, Changxi,She, Jiarong,Yuan, Youzhu
, p. 220 - 221 (2005)
MCM-41 mesoporous silicas-supported water-soluble TPPTS-Rh complex in the ionic liquid TMGL exhibited high performance and stability for the hydroformylation of 1-hexene, and the catalyst system could be reused many times without reducing the activity and selectivity. Copyright
Rh/Cu2O nanoparticles: Synthesis, characterization and catalytic application as a heterogeneous catalyst in hydroformylation reaction
Jagtap, Samadhan A.,Bhosale, Manohar A.,Sasaki, Takehiko,Bhanage, Bhalchandra M.
, p. 162 - 168 (2016)
In this work, we report a rapid protocol for the synthesis of Rh/Cu2O nanoparticles (Rh/Cu2O NPs) in aqueous medium using microwave route. The microwave energy acts as driving force in synthesis which makes the process economical. The obtained nanoparticles were characterized with the help of FEG-SEM, TEM, HRTEM, EDS, XRD, FT-IR and ICP-AES techniques. The prepared Rh/Cu2O nanoparticles gave 100% yield of uniform spherical morphology. This is a simple, inexpensive and time saving protocol for synthesis of Rh/Cu2O nanoparticles than conventional methods. Furthermore, we showed the catalytic application of Rh/Cu2O nanoparticles in hydroformylation reaction for the conversion of 1-hexene to 1-hexanal at mild reaction conditions such as Rh/Cu2O NPs (10 mg), 35 bar pressure of H2/CO at 360 K. The reaction provides 99% conversion and high selectivity (>90%) toward aldehydes with branched aldehyde is a major product. Notably the reaction does not require the any phosphine ligand source, low catalyst loading, low temperature with major advantage of catalyst recyclability.
Synthesis, Structural Characterization, and Hydroformylation Activity of Rhodium(I) Complexes with a Polar Phosphinoferrocene Sulfonate Ligand
Zábransky, Martin,Císa?ová, Ivana,Trzeciak, Anna M.,Alsalahi, Waleed,?těpni?ka, Petr
, p. 479 - 488 (2019)
1′-(Diphenylphosphino)ferrocene-1-sulfonic acid (HL), isolated from the salt (Et3NH)L on an ion exchanger, reacts with Rh(I) complexes [Rh(acac)(CO)(PR3)] (acac = acetylacetonato-κ2O,O′) to give complexes of the type [Rh(CO)(PR3)(Ph2PfcSO3-κ2O,P)] (1a-d; R = Ph (a), Cy (b), 2-furyl (c), and OMe (d); fc = ferrocene-1,1′-diyl). In an analogous reaction with [Rh(acac)(nbd)] (nbd = n 2: n 2-norbornadiene), HL produces [Rh(nbd)(Ph2PfcSO3-κ2O,P)] (2). Adding (Et3NH)L (2 equiv per Rh) to [Rh(μ-Cl)(CO)2]2 and [Rh(acac)(CO)2] gives rise to the cationic complexes trans-(Et3NH)2[RhCl(CO)(Ph2PfcSO3-κP)2] (3) and (Et3NH)[Rh(CO)(Ph2PfcSO3-κ2O,P)(Ph2PfcSO3-κP)] (4), respectively. In complex 4, resulting from the simultaneous substitution of a CO ligand and acid-base replacement of the acac ligand, the P-monodentate and O,P-chelating phosphinoferrocene sulfonate ligands rapidly interconvert (in a solution). All compounds were characterized by spectroscopic methods and by elemental analysis, and the crystal structures of 1a·Me2CO, solvated 1b, 2, and 4·H2O were determined. Furthermore, the catalytic activity of all Rh(I) complexes was assessed in hydroformylation of vinyl acetate under solvent-free conditions at 80 °C and at 20 bar of synthesis gas (H2/CO = 1:1). High conversion with good selectivity to iso-aldehyde was observed for 1a·1/2H2O and 4·1/2H2O. When applied to "on-water" hydroformylation of 1-hexene (80 °C/10 bar), the complexes mainly promoted 1-hexene isomerization to 2-hexene. However, two of them, 1a·1/2H2O and 1c, exhibited reasonable selectivity to aldehydes and preferentially produced the linear product (n/iso ratios up to 3).
Reactions of stabilized Criegee intermediates from the gas-phase reactions of O3 with selected alkenes
Baker,Aschmann,Arey,Atkinson
, p. 73 - 85 (2002)
The gas-phase reactions of O3 with 1-octene, trans-7-tetradecene, 1,2-dimethyl-l-cyclohexene, and α-pinene have been studied in the presence of an OH radical scavenger, primarily using in situ atmospheric ionization tandem mass spectrometry (API-MS), to investigate the products formed from the reactions of the thermalized Criege intermediates in the presence of water vapor and 2-butanol (1-octene and trans-7-tetradecene forming the same Criege intermediate). With H3O+(H2O)n as the reagent ions, ion peaks at 149 u ([M + H]+) were observed in the API-MS analyses of the l-octene and trans-7-tetradecene reactions, which show a neutral loss of 34 u (H2O2) and are attributed to the α-hydroxyhydroperoxide CH3(CH2)5CH(OH)OOH, which must therefore have a lifetime with respect to decomposition of tens of minutes or more. No evidence for the presence of α-hydroxyhyroperoxides was obtained in the 1,2-dimethyl-1-cyclohexene or α-pinene reactions, although the smaller yields of thermalized Criegee intermediates in these reactions makes observation of α-hydroxyhydroperoxides from these reactions less likely than from the 1-octene and trans-7-tetradecene reactions. Quantifications of 2,7-octanedione from the 1,2-dimethyl-1-cyclohexene reactions and pinonaldehyde from the α-pinene reactions were made by gas chromatographic analyses during reactions with cyclohexane and with 2-butanol as the OH radical scavenger. The measured yields of 2,7-octanedione from 1,2-dimethyl-1-cyclohexene and of pinonaldehyde from α-pinene were 0.110 ± 0.020 and 0.164 ± 0.029, respectively, and were independent of the OH radical scavenger used. Reaction mechanisms are presented and discussed.
Anisole: A further step to sustainable hydroformylation
Delolo, Fábio G.,Dos Santos, Eduardo N.,Gusevskaya, Elena V.
, p. 1091 - 1098 (2019)
Hydroformylation, also known as the "oxo" process, is a major industrial process that employs rhodium or cobalt catalysts in solution; therefore the solvent of this process is a critical issue for its sustainability. Although several innovative solutions have been proposed recently, traditional fossil-derived solvents dominate the scenario for this reaction. In this paper, we studied a series of solvents considered more sustainable in recent ranks in the hydroformylation of a series of olefins. Anisole, a solvent with an impressive sustainability rank and very scarcely exploited in hydroformylation, proved to be an excellent alternative for this reaction.
High-pressure investigations under CO/H2 of rhodium complexes containing hemispherical diphosphites
Semeril, David,Matt, Dominique,Toupet, Loic,Oberhauser, Werner,Bianchini, Claudio
, p. 13843 - 13849 (2010)
The two rhodium complexes [Rh(acac)(LR)] (LR=(S,S)-5, 11,17,23-tetra-tert-butyl-25,27-di(OR)-26,28-bis(1,1'-binaphthyl-2, 2'-dioxyphosphanyloxy)calix[4]arene; 6: R=benzyl, 7: R=fluorenyl), each based on a hemispherical chelator forming a pocket about the metal centre upon chelation, are active in the hydroformylation of 1-octene and styrene. As expected for this family of diphosphanes, both complexes resulted in remarkably high selectivity towards the linear aldehyde in the hydroformylation of 1-octene (l/b≈15 for both complexes). Linear aldehyde selectivity was also observed when using styrene, but surprisingly only 6 displayed a marked preference for the linear product (l/b=12.4 (6) vs. 1.9 (7)). A detailed study of the structure of the complexes under CO or CO/H2 in toluene was performed by high-pressure NMR (HP NMR) and FT-IR (HP-IR) spectroscopies. The spectroscopic data revealed that treatment of 6 with CO gave [Rh(acac)(CO) (I·1-Lbenzyl)] (8), in which the diphosphite behaves as a unidentate ligand. Subsequent addition of H2 to the solution resulted in a well-defined chelate complex with the formula [RhH(CO)2(Lbenzyl)] (9). Unlike 6, treatment of complex 7 with CO only led to ligand dissociation and concomitant formation of [Rh(acac)(CO)2], but upon addition of H2 a chelate complex analogous to 9 was formed quantitatively. In both [RhH(CO)2(L R)] complexes the diphosphite adopts the bis-equatorial coordination mode, a structural feature known to favour the formation of linear aldehydes. As revealed by variable-temperature NMR spectroscopy, these complexes show the typical fluxionality of trigonal bipyramidal [RhH(CO)2(diphosphane)] complexes. The lower linear selectivity of 7 versus 6 in the hydroformylation of styrene was assigned to steric effects, due to the pocket in which the catalysis takes place being less adapted to accommodate CO or larger olefins and, therefore, possibly leading to facile ligand decoordination. This interpretation was corroborated by an X-ray structure determination carried out for 7. Rhodium in confinement: As revealed by high-pressure NMR/IR spectroscopic studies, the reaction of rhodium complexes containing hemispherical diphosphites with CO/H2 leads to trigonal bipyramidal intermediates in which the phosphorus atoms exclusively occupy equatorial sites (see figure). The resulting metal confinement selectively drives olefin hydroformylation reactions to form aldehydes that best fit the cavity. Copyright
On rhodium complexes bearing H-spirophosphorane derived ligands: Synthesis, structural and catalytic properties
Skarzyńska, Anna,Mieczynska, Ewa,Siczek, Miosz
, p. 179 - 186 (2013)
We investigated the coordination properties of H-spirophosphoranes towards rhodium ion. Symmetrical phosphorus ligands: HP(OCH2CH 2NH)2 L1, HP(OCH2CM-2NH)2 L2, HP(OCMe2CMe 2O)2 L3, HP(OC6H4NH)2 L4, and unsymmetrical phosphorus ligands: HP(OCMe2CMe2O)(OCH2CM-2NH) L5, HP(OCMe2CMe2O)(OC6H4NH) L6 were found to coordinate to rhodium precursor [Rh(CO)2Cl]2 exclusively in protonated k2-P,E (E =N, O) bidentate fashion, yielding complexes [Rh(CO)ClL] 1-6. The complexes were characterised by spectroscopic methods. The molecular structures of the ligand L6 complexes 3, 5 and 6 were determined by single-crystal X-ray diffraction. The catalytic activity of the complexes was determined in hydroformylation reaction of 1-hexene. Complexes 1 and 2 appeared to be active in isomerisation reactions yielding 76 and 62% of 2-hexene. When used with six-fold excess of triphenylphosphite P(OPh)3 as a modified ligand, the most active catalyst 1 in hydroformylation reaction produced 66% of aldehydes and 22% of 2-hexene.
Tris(2-pyridyl)phosphine Complexes of Ruthenium(II) and Rhodium(I). Hydroformylation of Hex-1-ene by Rhodium Complexes
Kurtev, Kurti,Ribola, Dominique,Jones, Richard A.,Cole-Hamilton, David J.,Wilkinson, Geoffrey
, p. 55 - 58 (1980)
Complexes of ruthenium(II) and rhodium(I) containing tris(2-pyridyl)phosphine are described, examples being RuHCl3 and RhCl2.In certain cases, as in these, the nitrogen atom of one of the 2-pyridyl groups can act as a donor to give a P,N chelate ligand.In the presence of an excess of P(py)3 and at low CO + H2 (1 : 1) pressures, the complex RhH(CO)(PPh3)2 acts as a catalyst for the selective hydroformylation of hex-1-ene to n-heptanal.
Tri(3-pyridyl)phosphine as amphiphilic ligand in the rhodium-catalysed hydroformylation of 1-hexene
Meyer, Wolfgang H.,Bowen, Richard J.,Billing, David G.
, p. 339 - 345 (2007)
The molecular structure of carbonylchlorobis(tri(3-pyridyl)phosphine) rhodium, 1, has been determined by X-ray diffraction methods. The N-protonated trifluoromethanesulfonate (triflate) complex 3 was synthesised as a model compound for the extraction of a rhodium complex bearing amphiphilic ligands which can allow catalyst recycling in the hydroformylation of alkenes by using their distribution behavior in organic and aqueous solvents of different pH. The high water-solubility of the employed ligand renders the recycling method as only partly successful due to insufficient extraction from the water phase into the organic phase. In the hydroformylation of 1-hexene the production of rt-heptanal is slightly disfavoured when using the ligand tri(3-pyridyl) phosphine as compared to triphenylphosphine which can be ascribed to a higher amount of ligand-deficient active rhodium complexes of the less basic pyridyl phosphine ligand under CO pressure.
Benzoquinones from Embelia angustifolia
Lund, Anne-Kristine,Lemmich, John,Adsersen, Anne,Olsen, Carl E.
, p. 679 - 681 (1997)
Three new 2,5-dihydroxy-3-alkyl-1,4-benzoquinones, (Z)-2,5-dihydroxy-3- (pentadec-8-enyl)-1,4-benzoquinone, (Z,Z)-2,5-dihydroxy-3-(heptadeca-8,11- dienyl)-1,4-benzoquinone and (Z)-2,5-dihydroxy-3-(heptadec-8-enyl)-1,4- benzoquinone and the known 2,5-dihydroxy-3-pentadecyl-1,4-benzoquinone were isolated from the leaves of Embelia angustifolia. Their structures have been established on the basis of spectral analysis and by chemical methods.
Decreasing Side Products and Increasing Selectivity in the Tandem Hydroformylation/Acyloin Reaction
Ostrowski, Karoline A.,Fassbach, Thiemo A.,Vogelsang, Dennis,Vorholt, Andreas J.
, p. 2607 - 2613 (2015)
A highly selective catalyst system was developed for the recently discovered tandem hydroformylation/acyloin reaction by systematic investigations and changes of reaction conditions. This new catalyst system is characterized by an excellent selectivity of the desired reaction pathway with negligible amounts of side products. A successful application of the tandem hydroformylation/acyloin reaction to a variety of olefins is enabled with comparable excellent selectivities up to >99% for the first and second reaction step, therefore a general synthesis for the conversion of olefins into acyloins is found. Furthermore, very good to excellent yields for the intermediates and final acyloin products were observed within two catalysed reactions in one preparative step. The acyloin product was applied as a nonpolar precursor for surfactants. After attaching a polar head group to the acyloin and determination of tensiometric data, the molecule showed industrial relevant surface-active properties. Jointly successful: New catalyst systems for the tandem hydroformylation/acyloin reaction display excellent selectivities within two catalyzed reactions in one preparative step. A variety of olefins can be converted efficiently, and the acyloin product is applied successfully as a nonpolar precursor for surfactants.
Synthesis of electron-withdrawing butane- and arene-sulfonylamino phosphines and use in rhodium-catalyzed hydroformylation
Magee, Matthew P.,Li, Huan-Qiu,Morgan, Oma,Hersh, William H.
, p. 387 - 394 (2003)
Reaction of RSO2N(H)CH2CH2N(H)SO2R [R = Bu (1), 4-nitrobenzene (7), 1-naphthalene (9a), 2-naphthalene (9b)] with PhPCl2 or EtPCl2 gives monodentate phosphorus compounds 2 and 3 (R = Bu, PhP and EtP), and 8 (R = 4-nitrobenzene, PhP), and with Ph2PCl gives the corresponding bidentate phosphine ligands Ph2PN(SO2R)CH2CH2N(SO2R)P Ph2 [R = Bu (10), 4-nitrobenzene (11), 1- and 2-naphthalene (12a,b)]; similar reactions of N,N′-(1-butanesulfonyl)-2,2′-diaminobiphenyl (4) give monodentate 5 (PhP) and 6 (EtP) and N,N′-bis(diphenylphosphino)-N,N′-(1-butanesulfonyl)-2,2′-diami nobiphenyl (16). A monodentate analogue of 10 was also prepared, Ph2PN(Et)SO2Bu (14). Diphosphorus compounds with two butanesulfonylamino groups on phosphorus were also prepared from 1 and Cl2P(CH2)nPCl2 (n = 2, 4) to give 19 and 20. Details of the 13C NMR false AA′X systems are reported for 19 and 20. Rhodium-catalyzed hydroformylation reactions were run at 60 and 80 °C, at CO/H2 pressures from 4-11 atm, and in THF, toluene, CH2Cl2, and dioxane. Results show that the highest ratios of linear (n) to branched (iso) aldehydes were obtained with arenesulfonamides (n:iso > 10) while the bidentate alkanesulfonamide 10 gave a lower n:iso ratio of 7.2 but the highest rate [k1 = 1.98 h-1, turnover frequency = 1130 mol aldehyde (mol Rh)-1 h-1] in THF at 80 °C. Both the rate and n:iso ratio for 10 were found to increase with decreasing CO/H2 pressure in THF and in toluene, although the rate change was small for toluene. Both the rate and n:iso ratio for 10 also increased in CH2Cl2, but this was found not to be due to lower CO/H2 concentrations in solution, on the basis of solubility measurements in THF and CH2Cl2.
Solvent-free oxidation of straight-chain aliphatic primary alcohols by polymer-grafted vanadium complexes
Chaudhary, Nikita,Haldar, Chanchal,Kachhap, Payal
, (2021/12/02)
Oxidovanadium(IV) complexes [VO(tertacac)2] (1), [VO(dipd)2] (2), and [VO(phbd)2] (3) were synthesized by reacting [VO(acac)2] with 2,2,6,6-tetramethyl-3,5-hepatanedione, 1,3-diphenyl-1,3-propanedione, and 1-phenyl-1,3-butanedione, respectively. Imidazole-modified Merrifield resin was used for the heterogenization of complexes 1–3. During the process of heterogenization, the V4+ center in complex 2 converts into V5+, whereas the other two complexes 1 and 3 remain in the oxidovanadium(IV) state in the polymer matrix. Theoretically, calculated IPA values of 1–3 suggest that 2 is prone to oxidation compared with 1 and 3, which was also supported by the absence of EPR lines in 5. Polymer-supported complexes Ps-Im-[VIVO(tertacac)2] (4), Ps-Im-[VVO2(dipd)2] (5), and Ps-Im-[VIVO(phbd)2] (6) were applied for the solvent-free heterogenous oxidation of a series of straight-chain aliphatic alcohols in the presence of H2O2 at 60°C and showed excellent substrate conversion specially for the alcohols with fewer carbon atoms. Higher reaction temperature improves the substrate conversion significantly for the alcohols containing more carbon atoms such as 1-pentanol, 1-hexanol, and 1-heptanol while using optimized reaction conditions. However, alcohols with fewer carbon atoms seem less affected by reaction temperatures higher than the optimized temperature. A decreasing trend in the selectivity(%) of carboxylic acid was observed with increasing carbon atoms among the examined alcohols, whereas the selectivity towards aldehydes increased. The order of efficiency of the supported catalysts is 4 > 6 > 5 in terms of turnover frequency (TOF) values and substrate conversion, further supported by theoretical calculations.
Methyl-modified cage-type phosphorus ligand and preparation method thereof Preparation method and application thereof
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Paragraph 0075-0084; 0087-0088, (2021/09/15)
The invention discloses a methyl-modified cage-type phosphorus ligand, a preparation method and application thereof, in particular to a synthesis design, wherein methyl is further introduced on a phenyl ring of triphenylphosphine, and a methyl-modified cage-type phosphorus ligand is synthesized, and when a methyl meta-substituted cage-type phosphorus ligand is used as a hydroformylation reaction catalyst the proportion of n-structural aldehyde and isomeric aldehyde is 2.6. TOF-1 The methyl-substituted cage-type phosphorus ligand is excellent in performance, stable in property and recyclable, has excellent substrate applicability in the hydroformylation catalytic reaction, has a good industrial application prospect, and has very important significance in metal organic catalysis.