0000000000266348

AUTHOR

Ma Angeles ÚBeda

Enantio- and Diastereocontrol in Intermolecular Cyclopropanation Reaction of Styrene Catalyzed by Dirhodium(II) Complexes with Bulky ortho-Metalated Aryl Phosphines:  Catalysis in Water as Solvent. Study of a (+)-Nonlinear Effect

Enantiomerically pure dirhodium(II) complexes with ortho-metalated para-substituted aryl phosphines have been shown to lead to an enantio- and diastereoselective cyclopropanation of styrene with ethyl diazoacetate. Enantioselectivities up to 91% and diastereoselectivities up to 90% are observed for ethyl cis-2-phenylcyclopropanecarboxylate. High enantio- and diastereoselectivities are observed for the synthesis of ethyl cis-2-phenylcyclopropanecarboxylate using water as solvent. Additionally, a (+)-nonlinear effect, (+)-NLE, has been observed and studied in the asymmetric catalytic reaction developed in n-pentane.

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Immobilized Chiral ortho-Metalated Dirhodium(II) Compounds as Catalysts in the Asymmetric Cyclopropanation of Styrene with Ethyl Diazoacetate

Immobilization of ortho-metalated dirhodium(II) compounds has been achieved by a carboxylate interchange reaction between (M)-Rh2(l-protos)2[(p-XC6H3)P(p-XC6H4)2]2 diastereoisomers and carboxyethylpolystyrene polymer (PS-C6H4(CH2)2CO2H). The immobilized chiral catalysts have been tested in the standard reaction of asymmetric cyclopropanation of styrene with ethyl diazoacetate, giving higher yields than homogeneous chiral trifluoroacetate derivatives, but their diastereo- and enantioselectivities were lower. Some of the immobilized catalysts have proved to be very robust. The catalytic behavior of (M)-Rh2(O2C(CH2)2C6H5)2[(p-XC6H3)P(p-XC6H5)2]2 compounds has been studied as a model for the im…

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Dinuclear Palladium(II) and -(III) Compounds with O,O-Chelating Ligands. Room-Temperature Direct 2-Phenylation of 1-Methylindole

New dinuclear palladium(III) compounds of general formula Pd2[(C6H4)PPh2]2[O–O]2Cl2, O–O being chelating phenolates C6H4OC(O)R (R = CH3, 3a; R = C2H5, 3b; R = OPh, 3c) or acetylacetonates RC(O)CHC(O)R (R = CH3, 4a; R = CF3, 4b; R = C(CH3)3, 4c), have been obtained by oxidation with PhICl2 of the corresponding palladium(II) compounds. The stability of the new compounds has been studied by 31P NMR spectroscopy from 200 to 298 K. DFT calculations of the stability of the complexes have also been performed. In agreement with these calculations, only compound Pd2[(C6H4)PPh2]2[(CF3C(O)CHC(O)CF3]2Cl2, 6b, showed the highest thermal stability. 6b was characterized by X-ray diffraction methods, prese…

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Triazenides as Suitable Ligands in the Synthesis of Palladium Compounds in Three Different Oxidation States: I, II, and III

New orthometalated dinuclear triazenide palladium(II) compounds of the general formula Pd2[(C6H4)PPh2]2[R–N–N–N–R]2 (R = C6H5, 3a; o-BrC6H4, o-3b; o-MeOC6H4, o-3c; o-MeC6H4, o-3d ; p-BrC6H4, p-3b; p-MeOC6H4, p-3c; p-MeC6H4, p-3d) have been synthesized and structurally characterized. The characteristics of these compounds were compared with the isoelectronic formamidinate derivatives. These triazenide compounds have been suitable starting products in the synthesis of new not so common dinuclear palladium(I) compounds and new unusual palladium(III) ones. In the presence of an excess of the triazenide ligand, compounds o-3b and o-3c underwent a reduction process giving dinuclear palladium(I) c…

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Further orthometalated dinuclear palladium(iii) compounds with bridging N,S-donor ligands

New dinuclear palladium(III) compounds of general formula Pd2[(C6H4)PPh2]2[N-S]2Cl2, N-S being 2-mercaptopyridinate, 3a; 2-mercapto-6-methylpyridinate, 3b; 2-quinolinethiolate, 3c; 2-mercaptopyrimidinate, 3d; 1-methyl-1H-imidazole-2-thiolate, 3e; 1-methyl-1H-benzimidazole-2-thiolate, 3f; 2-mercaptobenzothiazolate, 3g and 5-mercapto-1-methyltetrazolate, 3h have been obtained by oxidation with PhICl2 of the corresponding palladium(II) counterparts. The stability of the new compounds has been studied by (31)P NMR spectroscopy from 200 to 298 K. Compounds 3f-h were relatively stable until room temperature and they have been synthesized and characterized by (31)P, (1)H and (13)C NMR spectroscopy…

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Benzoato and Thiobenzoato Ligands in the Synthesis of Dinuclear Palladium(III) and ‐(II) Compounds: Stability and Catalytic Applications

New palladium(III) compounds of formula Pd2[(C6H4)PPh2]2[OXC(C6H5)]2Cl2 [3a (X = O); 3b (X = S)] were obtained by the oxidation of the analogous palladium(II) ones with PhICl2 and were characterized by 31P, 1H, and 13C NMR spectroscopy at 223 K. Compound 3a was also structurally characterized by single-crystal X-ray diffraction methods, which revealed a Pd–Pd distance of 2.5212(10) A. DFT calculations were conducted to study the stability of all of these new palladium(III) and -(II) compounds with focus on the influence of the OS substitution of the donor atom in the ligand. The palladium(II) compounds Pd2[(C6H4)PPh2]2[OXC(C6H5)]2 [2a (X = O), 2b (X = S)] were also tested as precatalyst in …

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ortho-Metalated Dirhodium(II) Catalysts Immobilized on a Polymeric Cross-Linked Support by Copolymerization. Study of their Catalytic Activity in the Asymmetric Cyclopropanation of Styrene with Ethyl Diazoacetate

Chiral ortho-metalated dirhodium(II) compounds containing the phosphine P(p-CH2═CHC6H4)3 have been efficiently immobilized by radical copolymerization with styrene and 1,4-divinylbenzene. Their cat...

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Dinuclear Ortho-Metalated Palladium(II) Compounds with N,N- and N,O-Donor Bridging Ligands. Synthesis of New Palladium(III) Complexes

New dinuclear ortho-metalated palladium(II) compounds with N,N′-diarylformamidinates, Pd2[(C6H4)PPh2]2[R′NC(H)NR′]2 (R′ = C6H5, 3a; R′ = p-CH3C6H4, 3b; R′ = p-CH3OC6H4, 3c) and N,O-donor ligands, Pd2[(C6H4)PPh2]2[N,O]2 (N,O = succinimidate (5), phtalimidate (6), 2-hydroxypyridinate (7), acetanilidate (8)) have been synthesized and characterized by NMR spectroscopy and X-ray diffraction methods. The oxidation with iodobenzene dichloride gave new and rare Pd26+ compounds, Pd2[(C6H4)PPh2]2[R′NC(H)NR′]2Cl2 (R′ = C6H5, 4a; R′ = p-CH3C6H4, 4b). DFT calculations on the Pd24+ → Pd26+ oxidation reaction show that the substituents on the amidinate N atoms have a greater effect on the reaction energy …

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CCDC 996516: Experimental Crystal Structure Determination

Related Article: Susana Ibañez, Larisa Oresmaa, Francisco Estevan, Pipsa Hirva, Mercedes Sanaú, Ma Angeles Úbeda|2014|Organometallics|33|5378|doi:10.1021/om500702j

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CCDC 944605: Experimental Crystal Structure Determination

Related Article: Francisco Estevan, Pipsa Hirva, Mercedes Sanaú, MaAngeles Úbeda|2018|Organometallics|37|2980|doi:10.1021/acs.organomet.8b00342

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CCDC 944602: Experimental Crystal Structure Determination

Related Article: Francisco Estevan, Pipsa Hirva, Mercedes Sanaú, MaAngeles Úbeda|2018|Organometallics|37|2980|doi:10.1021/acs.organomet.8b00342

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CCDC 1052931: Experimental Crystal Structure Determination

Related Article: Francisco Estevan, Susana Ibáñez, Albert Ofori, Pipsa Hirva, Mercedes Sanaú and Ma Angeles Úbeda|2015|Eur.J.Inorg.Chem.||2822|doi:10.1002/ejic.201500324

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CCDC 996514: Experimental Crystal Structure Determination

Related Article: Susana Ibañez, Larisa Oresmaa, Francisco Estevan, Pipsa Hirva, Mercedes Sanaú, Ma Angeles Úbeda|2014|Organometallics|33|5378|doi:10.1021/om500702j

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CCDC 944603: Experimental Crystal Structure Determination

Related Article: Francisco Estevan, Pipsa Hirva, Mercedes Sanaú, MaAngeles Úbeda|2018|Organometallics|37|2980|doi:10.1021/acs.organomet.8b00342

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CCDC 944600: Experimental Crystal Structure Determination

Related Article: Francisco Estevan, Pipsa Hirva, Mercedes Sanaú, MaAngeles Úbeda|2018|Organometallics|37|2980|doi:10.1021/acs.organomet.8b00342

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CCDC 1052933: Experimental Crystal Structure Determination

Related Article: Francisco Estevan, Susana Ibáñez, Albert Ofori, Pipsa Hirva, Mercedes Sanaú and Ma Angeles Úbeda|2015|Eur.J.Inorg.Chem.||2822|doi:10.1002/ejic.201500324

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CCDC 996518: Experimental Crystal Structure Determination

Related Article: Susana Ibañez, Larisa Oresmaa, Francisco Estevan, Pipsa Hirva, Mercedes Sanaú, Ma Angeles Úbeda|2014|Organometallics|33|5378|doi:10.1021/om500702j

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CCDC 996517: Experimental Crystal Structure Determination

Related Article: Susana Ibañez, Larisa Oresmaa, Francisco Estevan, Pipsa Hirva, Mercedes Sanaú, Ma Angeles Úbeda|2014|Organometallics|33|5378|doi:10.1021/om500702j

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CCDC 944604: Experimental Crystal Structure Determination

Related Article: Francisco Estevan, Pipsa Hirva, Mercedes Sanaú, MaAngeles Úbeda|2018|Organometallics|37|2980|doi:10.1021/acs.organomet.8b00342

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CCDC 1052932: Experimental Crystal Structure Determination

Related Article: Francisco Estevan, Susana Ibáñez, Albert Ofori, Pipsa Hirva, Mercedes Sanaú and Ma Angeles Úbeda|2015|Eur.J.Inorg.Chem.||2822|doi:10.1002/ejic.201500324

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CCDC 996515: Experimental Crystal Structure Determination

Related Article: Susana Ibañez, Larisa Oresmaa, Francisco Estevan, Pipsa Hirva, Mercedes Sanaú, Ma Angeles Úbeda|2014|Organometallics|33|5378|doi:10.1021/om500702j

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CCDC 996520: Experimental Crystal Structure Determination

Related Article: Susana Ibañez, Larisa Oresmaa, Francisco Estevan, Pipsa Hirva, Mercedes Sanaú, Ma Angeles Úbeda|2014|Organometallics|33|5378|doi:10.1021/om500702j

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CCDC 944601: Experimental Crystal Structure Determination

Related Article: Francisco Estevan, Pipsa Hirva, Mercedes Sanaú, MaAngeles Úbeda|2018|Organometallics|37|2980|doi:10.1021/acs.organomet.8b00342

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