- Catalyst-Free Hydrodefluorination of Perfluoroarenes with NaBH4
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Presented is an economical means of removing fluorine from various highly fluorinated arenes using NaBH4. The procedure was adapted for different classes of perfluoroarenes. A novel isomer of an emerging class of organic dyes based on the carbazole phthalonitrile motif was succinctly synthesized in two steps from tetrafluorophthalonitrile, demonstrating the utility of the hydrodefluorination procedure. Initial exploration of the dye shows it to be photoactive and capable of facilitating contrathermodynamic styrenoid E/Z isomerization.
- Schoch, Timothy D.,Mondal, Mukulesh,Weaver, Jimmie D.
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supporting information
p. 1588 - 1593
(2021/03/03)
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- Directed synthesis of fluorine containing 2,3-dihydrobenzo[b][1,4]oxathiine derivatives from polyfluoroarenes
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Polyfluorinated 2,3-dihydrobenzo[b][1,4]oxathiines were synthesized starting from monosubstituted hexafluorobenzenes and 2-mercaptoethanol via aromatic nucleophilic substitution of fluorine atoms in good yields. The reactions take place under mild reaction conditions and require readily available starting materials. The possibility of structural modifications of the obtained heterocycles through interaction with phenylethylamine and potassium methylate was demonstrated.
- Politanskaya, Larisa,Tretyakov, Evgeny
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- Mn(i) organometallics containing the iPr2P(CH2)2PiPr2 ligand for the catalytic hydration of aromatic nitriles
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The first example of a homogeneous hydration of aromatic nitriles catalyzed by manganese molecular compounds is reported. The Mn(i) organometallics fac-[(CO)3Mn(dippe)(Z)]1-nX1-n (n = 0, 1; Z = Br, OTf, PhCN; X = OTf) were synthesized and characterized, and their reactivity was studied. The species fac-[(CO)3Mn(dippe)(OTf)] (2) was used as a catalyst precursor for the selective hydration of benchmark benzonitrile (2 mol% 2, THF/H2O 1:2 v/v, 18 h, 100 °C) to produce benzamide in 90% isolated yield. A series of (hetero)aromatic nitriles were hydrated to synthesize the corresponding amides in very good to excellent yields (88-94%). Isotopic labeling studies accounted for a proton transfer as the rate-determining step.
- Gardu?o, Jorge A.,Arévalo, Alma,Flores-Alamo, Marcos,García, Juventino J.
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p. 2606 - 2616
(2018/05/30)
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- Phosphinous Acid-Assisted Hydration of Nitriles: Understanding the Controversial Reactivity of Osmium and Ruthenium Catalysts
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The synthesis and catalytic behavior of the osmium(II) complexes [OsCl2(η6-p-cymene)(PR2OH)] [R=Me (2 a), Ph (2 b), OMe (2 c), OPh (2 d)] in nitrile hydration reactions is presented. Among them, the best catalytic results were obtained with the phosphinous acid derivative [OsCl2(η6-p-cymene)(PMe2OH)] (2 a), which selectively provided the desired primary amides in excellent yields and short times at 80 °C, employing directly water as solvent, and without the assistance of any basic additive (TOF values up to 200 h?1). The process was successful with aromatic, heteroaromatic, aliphatic, and α,β-unsaturated organonitriles, and showed a high functional group tolerance. Indeed, complex 2 a represents the most active and versatile osmium-based catalyst for the hydration of nitriles reported so far in the literature. In addition, it exhibits a catalytic performance similar to that of its ruthenium analogue [RuCl2(η6-p-cymene)(PMe2OH)] (4). However, when compared to 4, the osmium complex 2 a turned out to be faster in the hydration of less-reactive aliphatic nitriles, whereas the opposite trend was generally observed with aromatic substrates. DFT calculations suggest that these differences in reactivity are mainly related to the ring strain associated with the key intermediate in the catalytic cycle, that is, a five-membered metallacyclic species generated by intramolecular addition of the hydroxyl group of the phosphinous acid ligand to the metal-coordinated nitrile.
- González-Fernández, Rebeca,Crochet, Pascale,Cadierno, Victorio,Menéndez, M. Isabel,López, Ramón
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p. 15210 - 15221
(2017/10/12)
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- Synthesis and catalytic applications of ruthenium(ii)-phosphino-oxime complexes
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In this work, the preparation of the first ruthenium complexes containing a phosphino-oxime ligand is presented. Thus, the reaction of cis-[RuCl2(DMSO)4] (3) with 2.4 equivalents of 2-Ph2PC6H4CH=NOH (1) in refluxing THF led to the clean formation of the octahedral ruthenium(ii) derivative cis,cis,trans-[RuCl2{κ2-(P,N)-2-Ph2PC6H4CH=NOH}2] (5), whose structure was unambiguously confirmed by means of a single-crystal X-ray diffraction study. Complex 5 could also be synthesized from the reaction of the dimer [{RuCl(μ-Cl)(η6-p-cymene)}2] (4) with an excess of 1 in refluxing toluene. Treatment of 4 with 2 equivalents of 1, in CH2Cl2 at r.t., allowed also the preparation of the half-sandwich Ru(ii) derivative [RuCl{κ2-(P,N)-2-Ph2PC6H4CH=NOH}(η6-p-cymene)][PF6] (6). In addition, complexes 5 and 6 proved to be active catalysts for the rearrangement of aldoximes to primary amides, as well as for the α-alkylation/reduction of acetophenones with primary alcohols, with the former showing the best performances in both processes.
- Francos, Javier,Menéndez-Rodríguez, Lucía,Tomás-Mendivil, Eder,Crochet, Pascale,Cadierno, Victorio
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p. 39044 - 39052
(2016/06/01)
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- A mild hydration of nitriles catalysed by copper(ii) acetate
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A simple, mild and general procedure for the hydration of nitriles to amides using copper as catalyst and promoted by N,N-diethylhydroxylamine is described. The reaction can be conducted in water at low temperature in short reaction times. This new procedure allows amides to be obtained from a wide range of substrates in excellent yields.
- Marcé, Patricia,Lynch, James,Blacker, A. John,Williams, Jonathan M. J.
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supporting information
p. 1436 - 1438
(2016/01/25)
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- Chlorophosphines as auxiliary ligands in ruthenium-catalyzed nitrile hydration reactions: Application to the preparation of β-ketoamides
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The catalytic hydration of nitriles into amides, in water under neutral conditions, has been studied using a series of arene-ruthenium(ii) complexes containing commercially available chlorophosphines as auxiliary ligands, i.e. compounds [RuCl2(η6-p-cymene)(PR2Cl)] (R = aryl, heteroaryl or alkyl group). In the reaction medium, the coordinated chlorophosphines readily undergo hydrolysis to generate the corresponding phosphinous acids PR2OH, which are well-known "cooperative" ligands for this catalytic transformation. Among the complexes employed, best results were obtained with [RuCl2(η6-p-cymene){P(4-C6H4F)2Cl}]. Performing the catalytic reactions at 40 °C with 2 mol% of this complex, a large variety of organonitriles could be selectively converted into the corresponding primary amides in high yields and relatively short times. The application of [RuCl2(η6-p-cymene){P(4-C6H4F)2Cl}] in the preparation of synthetically useful β-ketoamides is also presented.
- González-Fernández, Rebeca,González-Liste, Pedro J.,Borge, Javier,Crochet, Pascale,Cadierno, Victorio
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p. 4398 - 4409
(2016/07/06)
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- Bis(allyl)-ruthenium(IV) complexes with phosphinous acid ligands as catalysts for nitrile hydration reactions
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Several mononuclear ruthenium(iv) complexes with phosphinous acid ligands [RuCl2(η3:η3-C10H16)(PR2OH)] have been synthesized (78-86% yield) by treatment of the dimeric precursor [{RuCl(μ-Cl)(η3:η3-C10H16)}2] (C10H16 = 2,7-dimethylocta-2,6-diene-1,8-diyl) with 2 equivalents of different aromatic, heteroaromatic and aliphatic secondary phosphine oxides R2P(O)H. The compounds [RuCl2(η3:η3-C10H16)(PR2OH)] could also be prepared, in similar yields, by hydrolysis of the P-Cl bond in the corresponding chlorophosphine-Ru(iv) derivatives [RuCl2(η3:η3-C10H16)(PR2Cl)]. In addition to NMR and IR data, the X-ray crystal structures of representative examples are discussed. Moreover, the catalytic behaviour of complexes [RuCl2(η3:η3-C10H16)(PR2OH)] has been investigated for the selective hydration of organonitriles in water. The best results were achieved with the complex [RuCl2(η3:η3-C10H16)(PMe2OH)], which proved to be active under mild conditions (60 °C), with low metal loadings (1 mol%), and showing good functional group tolerance.
- Tomás-Mendivil, Eder,Francos, Javier,González-Fernández, Rebeca,González-Liste, Pedro J.,Borge, Javier,Cadierno, Victorio
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p. 13590 - 13603
(2016/09/04)
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- Palladium(II) complexes with a phosphino-oxime ligand: Synthesis, structure and applications to the catalytic rearrangement and dehydration of aldoximes
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The treatment of [PdCl2(COD)] (COD = 1,5-cyclooctadiene) with 1 and 2 equivalents of 2-(diphenylphosphino)benzaldehyde oxime in dichloromethane at room temperature led to the selective formation of [PdCl2{κ2-(P,N)-2-Ph2PC6H4CHNOH}] (1) and [Pd{κ2-(P,N)-2-Ph2PC6H4CHNOH}2][Cl]2 (2), respectively, which represent the first examples of Pd(II) complexes containing a phosphino-oxime ligand. These compounds, whose structures were fully confirmed by X-ray diffraction methods, were active in the catalytic rearrangement of aldoximes. In particular, using 5 mol% complex 1, a large variety of aldoximes could be cleanly converted into the corresponding primary amides at 100 °C, employing water as solvent and without the assistance of any cocatalyst. Palladium nanoparticles are the active species in the rearrangement process. In addition, when the same reactions were performed employing acetonitrile as solvent, selective dehydration of the aldoximes to form the respective nitriles was observed. For comparative purposes, the catalytic behaviour of an oxime-derived palladacyclic complex has also been briefly evaluated.
- Menéndez-Rodríguez, Lucía,Tomás-Mendivil, Eder,Francos, Javier,Nájera, Carmen,Crochet, Pascale,Cadierno, Victorio
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p. 3754 - 3761
(2015/07/01)
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- Hydration of nitriles to amides by a chitin-supported ruthenium catalyst
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Chitin-supported ruthenium (Ru/chitin) promotes the hydration of nitriles to carboxamides under aqueous conditions. The nitrile hydration can be performed on a gram-scale and is compatible with the presence of various functional groups including olefins, aldehydes, carboxylic esters and nitro and benzyloxycarbonyl groups. The Ru/chitin catalyst is easily prepared from commercially available chitin, ruthenium(III) chloride and sodium borohydride. Analysis of Ru/chitin by high-resolution transmission electron microscopy indicates the presence of ruthenium nanoparticles on the chitin support.
- Matsuoka, Aki,Isogawa, Takahiro,Morioka, Yuna,Knappett, Benjamin R.,Wheatley, Andrew E. H.,Saito, Susumu,Naka, Hiroshi
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p. 12152 - 12160
(2015/02/19)
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- Exploring rhodium(I) complexes [RhCl(COD)(PR3)] (COD = 1,5-cyclooctadiene) as catalysts for nitrile hydration reactions in water: The aminophosphines make the difference
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Several rhodium(I) complexes, [RhCl(COD)(PR3)], containing potentially cooperative phosphine ligands, have been synthesized and evaluated as catalysts for the selective hydration of organonitriles into amides in water. Among the different phosphines screened, those of general composition P(NR 2)3 led to the best results. In particular, complex [RhCl(COD){P(NMe2)3}] was able to promote the selective hydration of a large range of nitriles in water without the assistance of any additive, showing a particularly high activity with heteroaromatic and heteroaliphatic substrates. Employing this catalyst, the antiepileptic drug rufinamide was synthesized in high yield by hydration of 4-cyano-1-(2,6- difluorobenzyl)-1H-1,2,3-triazole. For this particular transformation, complex [RhCl(COD){P(NMe2)3}] resulted more effective than related ruthenium catalysts.
- Tomas-Mendivil, Eder,Garcia-Alvarez, Rocio,Vidal, Cristian,Crochet, Pascale,Cadierno, Victorio
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p. 1901 - 1910
(2014/06/24)
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- An efficient ruthenium(iv) catalyst for the selective hydration of nitriles to amides in water under mild conditions
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A Ru(iv) catalyst able to promote the selective hydration of nitriles to amides in water, at low metal loadings and under mild conditions, is presented. This journal is the Partner Organisations 2014.
- Tomás-Mendivil, Eder,Suárez, Francisco J.,Díez, Josefina,Cadierno, Victorio
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supporting information
p. 9661 - 9664
(2014/08/18)
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- Investigation of binap-based hydroxyphosphine arene-ruthenium(II) complexes as catalysts for nitrile hydration
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The binap-based hydroxyphosphine-(η6-arene)-ruthenium(ii) complexes [RuX{η6:κ1(P)-PPh2-binaphthyl}{PPh2(OH)}][OTf] (X = OTf (4), Cl (5)) have been evaluated as potential catalysts for the selective hydration of nitriles to primary amides. The triflate derivative 4 proved to be the most active, being able to hydrate a large variety of aromatic, heteroaromatic, α,β-unsaturated and aliphatic nitriles in pure water at 100°C. The utility of complex 4 to promote the catalytic rearrangement of aldoximes has also been demonstrated. In addition, insights about the role played by the hydroxyphosphine ligand PPh2(OH) during the catalytic reactions are given.
- Toms-Mendivil, Eder,Menndez-Rodrguez, Luca,Francos, Javier,Crochet, Pascale,Cadierno, Victorio
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p. 63466 - 63474
(2015/02/19)
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- Ruthenium-catalyzed one-pot synthesis of primary amides from aldehydes in water
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The readily available arene-ruthenium(ii) complex [RuCl2(η 6-C6Me6){P(NMe2)3}] (5 mol%) proved to be an efficient catalyst for the direct synthesis of primary amides from aldehydes and hydroxylamine hydrochloride (NH2OH· HCl) in water at 100 °C. The process, which requires the presence of NaHCO3 to catch the HCl released during the formation of the key aldoxime intermediates, was operative with both aromatic, heteroaromatic, α,β-unsaturated and aliphatic aldehydes, and tolerated several functional groups. A greener approach using commercially available NH 2OH solution (50 wt.% in water) is also presented.
- Garcia-Alvarez, Rocio,Diaz-Alvarez, Alba E.,Crochet, Pascale,Cadierno, Victorio
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p. 5889 - 5894
(2013/05/09)
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- Thiazolyl-phosphine hydrochloride salts: Effective auxiliary ligands for ruthenium-catalyzed nitrile hydration reactions and related amide bond forming processes in water
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A series of water-soluble N-protonated thiazolyl-phosphine hydrochloride salts have been synthesized and coordinated to the ruthenium(ii) fragment [RuCl2(η6-p-cymene)]. The resulting complexes were evaluated as potential catalysts for the selective hydration of nitriles to primary amides in environmentally friendly aqueous medium. The best results in terms of activity were achieved when tris(5-(2-aminothiazolyl))phosphine trihydrochloride was used as ligand. Using the Ru(ii) complex 9 derived from this salt (3 mol%), the catalytic reactions proceeded cleanly in pure water at 100 °C without the assistance of any additive, affording the desired amides in high yields (>78%) after short reaction periods (0.5-7 h). The process was operative with both aromatic, heteroaromatic, α,β-unsaturated and aliphatic nitriles, and tolerated several functional groups. The utility of 9 in promoting the formation of primary amides in water by catalytic rearrangement of aldoximes and direct coupling of aldehydes with NH2OH·HCl has also been demonstrated.
- Garcia-Alvarez, Rocio,Zablocka, Maria,Crochet, Pascale,Duhayon, Carine,Majoral, Jean-Pierre,Cadierno, Victorio
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p. 2447 - 2456
(2013/09/12)
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- Ruthenium-catalyzed rearrangement of aldoximes to primary amides in water
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The rearrangement of aldoximes to primary amides has been studied using the readily available arene-ruthenium(II) complex [RuCl2(η 6-C6Me6){P(NMe2)3}] (5 mol %) as catalyst. Reactions proceeded cleanly in pure water at 100 °C without the assistance of any cocatalyst, affording the desired amides in high yields (70-90%) after short reaction times (1-7 h). The process was operative with both aromatic, heteroaromatic, α,β-unsaturated, and aliphatic aldoximes and tolerated several functional groups. Reaction profiles and experiments using 18O-labeled water indicate that two different mechanisms are implicated in these transformations. In both of them, nitrile intermediates are initially formed by dehydration of the aldoximes. These intermediates are then hydrated to the corresponding amides by the action of a second molecule of aldoxime or water. A kinetic analysis of the rearrangement of benzaldoxime to benzamide is also discussed.
- Garcia-Alvarez, Rocio,Diaz-Alvarez, Alba E.,Borge, Javier,Crochet, Pascale,Cadierno, Victorio
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p. 6482 - 6490
(2012/10/30)
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- Straightforward zinc-catalyzed transformation of aldehydes and hydroxylamine hydrochloride to nitriles
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In the present study, the zinc-catalyzed dehydration of a range of in situ generated aldoximes, available by the reaction of aldehydes and hydroxylamine hydrochloride, has been explored. After investigating various reaction parameters, with Zn(OTf)2 an excellent and easily accessible pre-catalyst was obtained. The system was highly active and dehydrated a broad range of aldoximes selectively to the corresponding nitriles under mild reaction conditions.
- Enthaler, Stephan,Weidauer, Maik,Schr?der, Fanny
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experimental part
p. 882 - 885
(2012/03/26)
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- Arene-ruthenium(II) complexes containing inexpensive tris(dimethylamino) phosphine: Highly efficient catalysts for the selective hydration of nitriles into amides
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The catalytic hydration of nitriles into amides, in water under neutral conditions, has been studied using a series of arene-ruthenium(II) derivatives containing the commercially available and inexpensive ligand tris(dimethylamino)phosphine. Among them, best results were obtained with the complex [RuCl2(η6-C6Me6) {P(NMe2)3}], which selectively provided the desired amides in excellent yields and short times (TOF values up to 11 400 h-1). The process was operative with both aromatic, heteroaromatic, aliphatic, and α,β-unsaturated organonitriles and showed a high functional group tolerance. The stability of [RuCl2(η6-C 6Me6){P(NMe2)3}] in water was evaluated, observing its progressive decomposition into the less-active dimethylamine-ruthenium(II) complex [RuCl2(η6-C 6Me6)(NHMe2)] by hydrolysis of the coordinated P(NMe2)3 ligand. The X-ray crystal structure determination of the toluene complex [RuCl2(η6-C6H 5Me){P(NMe2)3}] is also included.
- Garcia-Alvarez, Rocio,Diez, Josefina,Crochet, Pascale,Cadierno, Victorio
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experimental part
p. 5442 - 5451
(2011/12/13)
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- RUTHENIUM-BASED CATALYTIC COMPLEXES AND THE USE OF SUCH COMPLEXES FOR OLEFIN METATHESIS
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The invention relates to all compounds of the formula (I) or (II) in which: L is a neutral ligand; X, X′ are anionic ligands; R1 and R2 are, separately, a hydrogen, a C1-C6 alkyl, a C1-C6 perhalogenoalkyl, a aldehyde, a ketone, an ester, a nitrile, an aryl, a pyridinium alkyl, an optionally substituted C5 or C6 pyridinium alkyl, perhalogenoalkyl or cyclohexyl, a Cnh2NY radical 10 with n between 1 and 6 and y an i8onic marker, or a radical having the formula: wherein R1 can be a radical of formula (Ibis) when the compound has formula (I) or of formula (IIbis) when the compound has formula (II), R3 is a C1-C6 alkyl, or a C5 or C6 cycloalkyl or a C5 or C6 aryl; R0, R4, R5, R6, R7, R8, R9, R10, R11, are, separately, a hydrogen, C1-C6 alkyl, a C1-C6 perhalogenoalkyl, or a C5 or C6 aryl; wherein R9, R10, R11 can be a heterocycle; X1 is anion. R1 and R2 can form, with the N and the C to which they are attached, a heterocycle.
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-
- Arene-ruthenium(II) complexes containing amino-phosphine ligands as catalysts for nitrile hydration reactions
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Three different series of novel mononuclear arene-ruthenium(II) complexes containing amino-phosphine ligands, namely, [RuCl2{κ 1(P)-2-Ph2PC6H4CH 2NHR}(η6-arene)], [RuCl2{κ 1(P)-3-Ph2PC6H4CH 2NHR}(η6-arene)], and [RuCl2{κ 1(P)-4-Ph2PC6H4CH 2NHR}(η6-arene)] (arene = C6H6, p-cymene, 1,3,5-C6H3Me3, C6Me 6; R = iPr, tBu; all combinations), have been synthesized and fully characterized. These readily accessible species are efficient catalysts for the selective hydration of organonitriles into amides under challenging reaction conditions, i.e., pure aqueous medium in the absence of any cocatalyst, being much more active than their corresponding nonfunctionalized triphenylphosphine counterparts [RuCl2(PPh 3)(η6-arene)]. The results obtained in this study indicate that the (amino-phosphine)ruthenium(II) complexes operate through a "bifunctional catalysis" mechanism in which the ruthenium center acts as a Lewis acid, activating the nitrile molecule, and the P-donor ligand acts as a Brnsted base, the pendant amino group generating the real nucleophile of the hydration process, i.e., the OH- group.
- Garcia-Alvarez, Rocio,Diez, Josefina,Crochet, Pascale,Cadierno, Victorio
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experimental part
p. 3955 - 3965
(2010/12/25)
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- Benzamide Compounds Useful as High Potency Sweet Taste Enhancers
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The present invention relates to novel benzamide compounds may be used to provide desirable property of sweetness and to a foodstuff, chewing gum, medicinal product, toothpaste, alcoholic beverage, aqueous beverage, snack, sauce, confection, baked good, dairy product or cereal.
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- Selective ruthenium-catalyzed hydration of nitriles to amides in pure aqueous medium under neutral conditions
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A study was conducted to demonstrate that water-soluble ruthenium(II) complexes can be used as catalysts for the hydration of nitriles in pure aqueous media and under neutral conditions. The hydration of benzonitrile was investigated as a model reaction and the ruthenium precursor was added to a 0.33M aqueous solution of benzonitrile at 100°C, while the reaction was monitored by gas chromatography. All the complexes checked, were found to be active and selective catalysts in the hydration process, providing benzamide as a specific reaction product. The most relevant results were obtained by using ruthenium complexes, bearing a nitrogen-containing ligand, which led to appropriate production of benzamide. The most effective ruthenium complex was found to be an efficient catalyst for the selective hydration of a large number of other nitriles.
- Cadierno, Victorio,Francos, Javier,Gimeno, Jose
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scheme or table
p. 6601 - 6605
(2009/07/10)
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- Replacement of imine fragment in the ring of 2,6-disubstituted 1,4,3,5-octathiadiazine-4,4-dioxides in reaction with cyano-containing compounds
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Reactions of 2,6-disubstituted 1,4,3,5-octathiadiazine-4,4-dioxides with cyano-containing compounds (nitriles, thiocyanates, N,N-disubstituted cyanamides) proceeding with replacement of imine fragment in dioxide by corresponding fragment of cyanide were investigated. The limits of the reaction were revealed determined by electronic effects of substituents R1 and R2 in dioxide and R3 in cyanide. Transimination occurred in dioxides with strong electron-withdrawing substituents R 1 (CCl3, CBr3, C6F5)and weak acceptor or donor substituents R2 (4-NO2C 6H4, 4-ClC6H4, CH3) under the action of compounds R3C≡N with cyano groups of relatively high nucleophilicity (R3 = 4-ClC6H 4, C6H5, (CH3)2CHS, piperidino, morpholino, diethylamino), on the one hand, and with strong electron-withdrawing substituents R3 (CCl3) on the other hand.
- Utkina,Michurin,Shishulina
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p. 889 - 894
(2007/10/03)
-
- Fluorinated heterocyclic compounds. A photochemical synthesis of 3-amino-5-perfluoroaryl-1,2,4-oxadiazoles
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A photochemical methodology for the synthesis of 3-amino- (or 3-N-substituted amino) 5-pentafluorophenyl-1,2,4-oxadiazoles is reported. Irradiation of 3-pentafluorobenzoylamino-4-methyl-1,2,5-oxadiazole (Furazan) at 254 nm in methanol and in the presence of ammonia, primary or secondary aliphatic amines produces 3-amino-, 3-(N-alkylamino)-, 3-(N,N-dialkylamino)-5-pentafluorophenyl-1,2,4-oxadiazoles. The photoreaction follows the fragmentation pattern of the furazan ring with the extrusion of acetonitrile and the formation of a counterpart fragment which the nitrogen nucleophile will capture. Depending on the nature of the reagent, displacement of a fluoride anion at the C(5)-pentafluorophenyl moiety of the first-formed oxadiazoles by the nitrogen nucleophile and/or the solvent also takes place. By the same photochemical approach, the synthesis of the 3-methoxy-5-pentafluorophenyl-1,2,4-oxadiazole is also described.
- Buscemi, Silvestre,Pace, Andrea,Calabrese, Rosa,Vivona, Nicolò,Metrangolo, Pierangelo
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p. 5865 - 5871
(2007/10/03)
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- REACTIONS OF POLYFLUORINATED AROMATIC N,N-DICHLOROAMIDES AND N,N-DICHLOROAMINES WITH SULFUR AND SELENIUM AND THEIR ELECTRONIC STRUCTURE
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In the reaction of the N,N-dichloroamides of pentafluorobenzenesulfonic and pentafluorobenzoic acids with sulfur and selenium the corresponding iminosulfur and iminoselenium dichlorides are formed.It was found that polyfluorinated azobenzenes are formed in the reaction of N,N-dichloroamines of the polyfluorinated aromatic series with sulfur and selenium.The charges at the chlorine atoms of polyfluorinated aromatic N,N-dichloroamides and N,N-dichloroamines were determined on the basis of data from 35Cl NQR, the x-ray fluoroscence mechanism spectra of the chlorine, and quantum-chemical calculations by the CNDO/2 method.The mechanism of the reactions of polyfluorinated aromatic N,N-dichloroamides and N,N-dichloroamines with sulfur and selenium is discussed.
- Zibarev, A. V.,Dolenko, G. N.,Krupoder, S. A.,Mazalov, L. N.,Poleshchuk, O. Kh.,et al.
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p. 347 - 354
(2007/10/02)
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