51
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López-Rodríguez R, Ros A, Fernández R, Lassaletta JM. Pinacolborane as the Boron Source in Nitrogen-Directed Borylations of Aromatic N,N-Dimethylhydrazones. J Org Chem 2012; 77:9915-20. [DOI: 10.1021/jo301965v] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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52
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Monge D, Bermejo A, Vázquez J, Fernández R, Lassaletta JM. Design and synthesis of new bis-hydrazones and pyridine bis-hydrazones: application in the asymmetric Diels-Alder reaction. ARKIVOC 2012. [DOI: 10.3998/ark.5550190.0014.205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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53
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Francos J, Grande-Carmona F, Faustino H, Iglesias-Sigüenza J, Díez E, Alonso I, Fernández R, Lassaletta JM, López F, Mascareñas JL. Axially chiral triazoloisoquinolin-3-ylidene ligands in gold(I)-catalyzed asymmetric intermolecular (4 + 2) cycloadditions of allenamides and dienes. J Am Chem Soc 2012; 134:14322-5. [PMID: 22892048 DOI: 10.1021/ja3065446] [Citation(s) in RCA: 154] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The first highly enantioselective intermolecular (4 + 2) cycloaddition between allenes and dienes is reported. The reaction provides good yields of optically active cyclohexenes featuring diverse substitution patterns and up to three stereocenters. Key to the success of the process is the use of newly designed axially chiral N-heterocyclic carbene-gold catalysts.
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54
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Crespo-Peña A, Monge D, Martín-Zamora E, Alvarez E, Fernández R, Lassaletta JM. Asymmetric formal carbonyl-ene reactions of formaldehyde tert-butyl hydrazone with α-keto esters: dual activation by bis-urea catalysts. J Am Chem Soc 2012; 134:12912-5. [PMID: 22823936 DOI: 10.1021/ja305209w] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The dual activation of α-keto esters and formaldehyde tert-butyl hydrazone by BINAM-derived bis-ureas is the key to achieve high reactivity and excellent enantioselectivities in nucleophilic addition (formal carbonyl-ene reaction) to functionalized tertiary carbinols. Ensuing high-yielding diazene-to-aldehyde tranformations and subsequent derivatizations provides a direct entry to a variety of densely functionalized products.
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55
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Ros A, Estepa B, Bermejo A, Álvarez E, Fernández R, Lassaletta JM. Phosphino Hydrazones as Suitable Ligands in the Asymmetric Suzuki–Miyaura Cross-Coupling. J Org Chem 2012; 77:4740-50. [DOI: 10.1021/jo300548z] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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56
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Ros A, López-Rodríguez R, Estepa B, Álvarez E, Fernández R, Lassaletta JM. Hydrazone as the Directing Group for Ir-Catalyzed Arene Diborylations and Sequential Functionalizations. J Am Chem Soc 2012; 134:4573-6. [DOI: 10.1021/ja300308c] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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57
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Ros A, Estepa B, López-Rodríguez R, Álvarez E, Fernández R, Lassaletta JM. Use of Hemilabile N,N Ligands in Nitrogen-Directed Iridium-Catalyzed Borylations of Arenes. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201104544] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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58
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Ros A, Estepa B, López-Rodríguez R, Álvarez E, Fernández R, Lassaletta JM. Use of hemilabile N,N ligands in nitrogen-directed iridium-catalyzed borylations of arenes. Angew Chem Int Ed Engl 2011; 50:11724-8. [PMID: 21990021 DOI: 10.1002/anie.201104544] [Citation(s) in RCA: 147] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 09/09/2011] [Indexed: 11/07/2022]
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59
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Crespo-Peña A, Martín-Zamora E, Fernández R, Lassaletta JM. “On Water” Nucleophilic Addition of Formaldehyde N,N-Dialkylhydrazones to α-Keto Esters. Chem Asian J 2011; 6:2287-90. [DOI: 10.1002/asia.201100174] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Revised: 05/24/2011] [Indexed: 11/11/2022]
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60
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Magriz A, Gómez-Bujedo S, Álvarez E, Fernández R, Lassaletta JM. Phthalazin-2-ylidenes As Cyclic Amino Aryl Carbene Ligands in Rhodium(I) and Iridium(I) Complexes. Organometallics 2010. [DOI: 10.1021/om100723b] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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61
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Bermejo A, Ros A, Fernández R, Lassaletta JM. C2-symmetric bis-hydrazones as ligands in the asymmetric Suzuki-Miyaura cross-coupling. J Am Chem Soc 2009; 130:15798-9. [PMID: 18980320 DOI: 10.1021/ja8074693] [Citation(s) in RCA: 190] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Glyoxal bis-hydrazone derived from (S,S)-1-amino-2,5-diphenylpyrrolidine behaves as an excellent ligand for phosphine-free, asymmetric Suzuki-Miyaura cross couplings, thereby affording a variety of enantiomerically enriched biaryls with different substitution patterns. The high catalytic activity of the [PdCl2(bis-hydrazone)] complex allows reactions to be performed at room temperature, affording products with excellent enantioselectivities in all cases.
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62
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Iglesias-Sigüenza J, Ros A, Díez E, Alcarazo M, Álvarez E, Fernández R, Lassaletta JM. Synthesis, structure and properties of [1,2,4]triazolo[4,3-a]pyridin-3-ylidene rhodium and palladium complexes. Dalton Trans 2009:7113-20. [DOI: 10.1039/b907043e] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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63
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Iglesias-Sigüenza J, Ros A, Díez E, Magriz A, Vázquez A, Álvarez E, Fernández R, Lassaletta JM. C2-Symmetric S/C/S ligands based on N-heterocyclic carbenes: a new ligand architecture for asymmetric catalysis. Dalton Trans 2009:8485-8. [DOI: 10.1039/b910846g] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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64
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Ros A, Alcarazo M, Iglesias-Sigüenza J, Díez E, Álvarez E, Fernández R, Lassaletta JM. Stereoselective Synthesis of Rhodium(I) 4-(Dialkylamino)triazol-5-ylidene Complexes. Organometallics 2008. [DOI: 10.1021/om800533g] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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65
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Marqués-López E, Herrera RP, Fernández R, Lassaletta JM. Uncatalyzed Strecker-Type Reaction ofN,N-Dialkylhydrazones in Pure Water. European J Org Chem 2008. [DOI: 10.1002/ejoc.200800297] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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66
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Marqués-López E, Martín-Zamora E, Díez E, Fernández R, Lassaletta JM. Stereoselective, Temperature-Dependent [2+2] Cycloaddition ofN,N-Dialkylhydrazones toN-Benzyl-N-(benzyloxycarbonyl)aminoketene. European J Org Chem 2008. [DOI: 10.1002/ejoc.200800194] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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67
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Brehme R, Enders D, Fernandez R, Lassaletta JM. Aldehyde
N
,
N
‐Dialkylhydrazones as Neutral Acyl Anion Equivalents: Umpolung of the Imine Reactivity. European J Org Chem 2007. [DOI: 10.1002/ejoc.200700746] [Citation(s) in RCA: 165] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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68
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Ros A, Magriz A, Dietrich H, Lassaletta JM, Fernández R. Stereoselective synthesis of syn β-hydroxy cycloalkane carboxylates: transfer hydrogenation of cyclic β-keto esters via dynamic kinetic resolution. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.05.058] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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69
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Herrera RP, Monge D, Martín-Zamora E, Fernandez R, Lassaletta JM. Organocatalytic Conjugate Addition of Formaldehyde N,N-Dialkylhydrazones to β,γ-Unsaturated α-Keto Esters. Org Lett 2007; 9:3303-6. [PMID: 17658836 DOI: 10.1021/ol071292c] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
(1S,2R)-1-Aminoindan-2-ol-derived thioureas behave as efficient H-bonding organocatalysts for the nucleophilic conjugate addition of formaldehyde hydrazones to beta,gamma-unsaturated alpha-keto esters as enoate surrogates, affording the corresponding adducts in good yields and enantioselectivities.
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70
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Fernández R, Ros A, Magriz A, Dietrich H, Lassaletta JM. Enantioselective synthesis of cis-α-substituted cycloalkanols and trans-cycloalkyl amines thereof. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.04.075] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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71
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Monge D, Martín-Zamora E, Vazquez J, Alcarazo M, Alvarez E, Fernandez R, Lassaletta JM. Enantioselective Conjugate Addition ofN,N-Dialkylhydrazones to α-Hydroxy Enones‡. Org Lett 2007; 9:2867-70. [PMID: 17580886 DOI: 10.1021/ol071055+] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The activation of alpha-hydroxy enones by the Zn(OTf)2/tBuBOX catalyst enables the enantioselective conjugate addition of 1-methyleneaminopyrrolidine as a neutral d1 synthon. Experimental evidence supports a stereochemical model where a triflate ligand controls the geometry of the catalyst-substrate complex by means of a OH-OTf hydrogen bond. The synthesis of beta-cyano acids illustrates the potential of the methodology.
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72
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Roseblade SJ, Ros A, Monge D, Alcarazo M, Álvarez E, Lassaletta JM, Fernández R. Imidazo[1,5-a]pyridin-3-ylidene/Thioether Mixed C/S Ligands and Complexes Thereof. Organometallics 2007. [DOI: 10.1021/om070063r] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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73
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Gómez-Bujedo S, Alcarazo M, Pichon C, Alvarez E, Fernández R, Lassaletta JM. Isoquinolin-1-ylidenes as electronically tuneable ligands. Chem Commun (Camb) 2007:1180-2. [PMID: 17347732 DOI: 10.1039/b617037d] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The novel isoquinolin-1-ylidene ligands, introduced into Rh(I) complexes by exploiting the carbene-like reactivity of adducts , exhibit ligand properties similar to those of classic NHCs, and their electronic properties can be tuned by the introduction of electron-withdrawing or donating groups in the benzene ring.
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74
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Ros A, Monge D, Alcarazo M, Álvarez E, Lassaletta JM, Fernández R. Synthesis, Structure, and Applications of N-Dialkylamino-N‘-alkylimidazol-2-ylidenes as a New Type of NHC Ligands. Organometallics 2006. [DOI: 10.1021/om060788f] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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75
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Lassaletta JM, Schmidt RR. Glycosyl Imidates, 75. Synthesis of the Hexasaccharide Moiety of Globo H (Human Breast Cancer) Antigen. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/jlac.199619960913] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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