0000000001300478
AUTHOR
Miguel A. Sierra
Structure and photoreactivity of stable zwitterionic group 6 metal allenyls
The synthesis and mechanistic study of the unprecedented reactivity of a series of zwitterionic η(1)-metal allenyls are reported.
Synthesis of oxaspiranic compounds through [3 + 2] annulation of cyclopropenones and donor–acceptor cyclopropanes.
The Sc(OTf)3-catalyzed [3 + 2]-annulation reaction between cyclopropenones and donor–acceptor cyclopropanes is described. The process leads directly to the formation of 4-oxaspiro[2.4]hept-1-ene derivatives in good to excellent reaction yields. Density functional theory calculations suggest that the [3 + 2]-annulation pathway is strongly preferred over the possible [3 + 3]-process.
Fluorescence Quenching in BODIPYs Having Ir‐ and Rh‐Tethered Complexes
The effect of Rh- and Ir-centers on the optical properties of the BODIPY core has been studied. To this end, novel metal complexes tethered to BODIPY have been prepared through an easy and versatile procedure using N-directed C–H activation reactions. The organometallic moiety has a tremendous influence on the emissive properties of the BODIPY fragment. A photoinduced electron transfer (PET) mechanism is suggested to be the main mechanism responsible for the suppression of the BODIPY fluorescence emission in the newly formed dyads. The efficiency of the PET depends on both the distance between the chromophores in the dyad and the nature of the transition metal (Rh vs. Ir).
On the Use of Metal Purine Derivatives (M=Ir, Rh) for the Selective Labeling of Nucleosides and Nucleotides
The reactions of neutral or cationic IrIII and RhIII derivatives of phenyl purine nucleobases with unsymmetrical alkynes produce new metallacycles in a predictable manner, which allows for the incorporation of either photoactive (anthracene or pyrene) or electroactive (ferrocene) labels in the nucleotide or nucleoside moiety. The reported methodology (metalation of the purine derivative and subsequent marker insertion) could be used for the postfunctionalization and unambiguous labeling of oligonucleotides.
Effect of a κ1-Bonded-M-1,2,3-triazole (M = Co, Ru) on the Structure and Reactivity of Group 6 Alkoxy (Fischer) Carbenes
The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.inorgchem. 6b02957. NMR data for the synthesized compounds, electrochemical data of azides 2 and 4 (PDF) Computational details and cif files containing crystal data for 3a and 5b (CIF1, CIF2)
Triazole vs. triazolium carbene ligands in the site-selective cyclometallation of o-carboranes by M(iii) (M = Ir, Rh) complexes
Ir(iii) and Rh(iii)-mediated site-selective cage B-H and C-H bond activation in o-carboranylmethyl derivatives has been achieved. The selectivity of the reaction is related to the electron donating properties of the ligand. 1,2,3-Triazole-derivatives use the N2 position of the triazole ring to direct the selective o-carborane B-H bond activation, whereas the corresponding triazolylidene derivatives lead to the cage C-H bond activation with complete site-selectivity.
Sequential Reactions of Alkynes on an Iridium(III) Single Site
Sequential insertion of terminal alkynes on IrIII cyclometalated complexes allow the formation of novel metallapolycycles in a controlled and efficient manner. ortho-Methylarylethynyl derivatives led to an unprecedented cascade combination of three fundamental processes (C−C bond formation, C(sp3)−H activation, and reductive coupling) on a single IrIII center, in a process compatible with functionalized biomolecules and photoactive substrates. The reaction with tert-butylacetylene led to a [6,5,4]-polycycle that incorporates an iridacyclobutenylidene in its structure. The sequence is a multicomponent reaction in which the metal not only promotes the different steps but also determines their…
An Entry to Mixed NHC-Fischer Carbene Complexes and Zwitterionic Group 6 Metal Alkenyls
The addition of NHCs to α,β-unsaturated Cr(0) and W(0) (Fischer) carbene complexes is strongly dependent on the electrophilicity of the carbene carbon. Electrophilic alkoxy-carbene complexes quantitatively react with NHCs to yield stable zwitterionic (racemic) Cr(0) - and W(0) -alkenyls with total regio- and E-stereoselectivity. Less electrophilic aminocarbenes react with NHCs to promote the displacement of a CO ligand and yield "mixed" NHC/Fischer biscarbenes in a process that is unprecedented in group 6 metal-carbene chemistry. In fact, the compounds prepared, are some of the scarce examples of Fischer bisylidenes reported in the literature. The electrochemistry of the zwitterionic Cr(0) …
Electrocatalytic Behavior of Tetrathiafulvalene (TTF) and Extended Tetrathiafulvalene (exTTF) [FeFe] Hydrogenase Mimics
TTF- and exTTF-containing [(μ-S2)Fe2(CO)6] complexes have been prepared by the photochemical reaction of TTF or exTTF and [(μ-S2)Fe2(CO)6]. These complexes are able to interact with PAHs. In the absence of air and in acid media an electrocatalytic dihydrogen evolution reaction (HER) occurs, similarly to analogous [(μ-S2)Fe2(CO)6] complexes. However, in the presence of air, the TTF and exTTF organic moieties strongly influence the electrochemistry of these systems. The reported data may be valuable in the design of [FeFe] hydrogenase mimics able to combine the HER properties of the [FeFe] cores with the unique TTF properties
Remote Control by π-Conjugation of the Emissive Properties of Fischer Carbene-BODIPY Dyads.
The synthesis, structure, and complete characterization of mono- and bimetallic dyads joining Fischer carbene complexes and BODIPY chromophores are reported. In these organometallic species, the Fischer carbene complex is attached to the BODIPY moiety through a p-aminophenyl group linked at the C8 carbon atom of the BODIPY core. The photophysical properties, namely the corresponding UV/vis absorption and emission spectra of these new metal-carbene complexes, are analyzed and discussed. It is found that whereas the absorption of the considered dyads strongly resembles that of the parent 4-anilinyl-substituted BODIPY, the fluorescence emission is significantly reduced in these species, very l…
Mono- and Bimetallic Zwitterionic Chromium(0) and Tungsten(0) Allenyls
A series of stable chiral (racemic), formally neutral, zwitterionic mono- and bimetallic M(CO)5[C(OEt)═C═CR(NHC)] (M = Cr, W) σ-allenyls are ready available by the addition of N-heterocyclic carbenes (NHCs) to Cr(0) and W(0) alkynyl Fischer carbene complexes. Different classes of NHCs, (e.g., 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene, 1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene, and their six- and seven-membered analogues and 1,3-bis(dimethyl)imidazol-2-ylidene) were employed as nucleophiles in these C-C bond-forming reactions yielding the novel complexes in essentially quantitative yields. A systematic experimental and computational study of the electronic properties of the C…
The selective synthesis of metallanucleosides and metallanucleotides: a new tool for the functionalization of nucleic acids.
Nucleobases team up: the efficient and selective preparation of purine-derived metallanucleosides, metallanucleotides, and metalladinucleotides having M-C bonds (M=Ir(III), Rh(III)) is reported for the first time. The results presented may be applied to the synthesis of functionalized nucleic acids, or DNA/RNA-modified segments.
Triazole-Containing [FeFe] Hydrogenase Mimics: Synthesis and Electrocatalytic Behavior
Through a Cu-catalyzed Huisgen cycloaddition between terminal alkynes and azides (CuAAC) reaction, azide [(μ-SCH2)2N(4-N3C6H4)Fe2(CO)6] has demonstrated to be a robust and versatile reagent able to...
Allergic Rhinitis and its Impact on Asthma (ARIA) Phase 4 (2018): Change management in allergic rhinitis and asthma multimorbidity using mobile technology
Allergic Rhinitis and its Impact on Asthma (ARIA) has evolved from a guideline by using the best approach to integrated care pathways using mobile technology in patients with allergic rhinitis (AR) and asthma multimorbidity. The proposed next phase of ARIA is change management, with the aim of providing an active and healthy life to patients with rhinitis and to those with asthma multimorbidity across the lifecycle irrespective of their sex or socioeconomic status to reduce health and social inequities incurred by the disease. ARIA has followed the 8-step model of Kotter to assess and implement the effect of rhinitis on asthma multimorbidity and to propose multimorbid guidelines. A second c…
A new family of "clicked" estradiol-based low-molecular-weight gelators having highly symmetry-dependent gelation ability.
Reported herein is the discovery of a novel family of "clicked" estradiol-based LMWGs whose gelation ability highly depends on the gelator symmetry. These LMWGs that gel different organic solvents in the presence of H(2)O even at concentrations as low as 0.04 wt% are readily accessible using "click" chemistry.
Revisiting the photochemical synthesis of [FeFe]-hydrogenase mimics: reaction optimization, mechanistic study and electrochemical behaviour
The photoreaction of [(μ-S)2Fe2(CO)6] and alkenes or alkynes has been optimized to readily obtain functionalized [FeFe]-hydrogenase mimics. Irradiation under low CO pressure in THF produces the corresponding photo-adducts in good/acceptable (alkenes/alkynes) yields, with retention of the starting olefin stereochemistry. DFT-calculations provide plausible reaction pathways in both, singlet and triplet states. The DFT-calculation based in the singlet state is energetically more favorable. The electrochemical behavior of the synthesized compounds is also presented, including studies in acidic media. The electrochemical properties of the products vary in the presence of a double bond (cycloaddi…
CCDC 1440542: Experimental Crystal Structure Determination
Related Article: Miguel A. Sierra, Alba D. Merinero, Elena A. Giner, Mar Gómez-Gallego, Carmen Ramírez de Arellano|2016|Chem.-Eur.J.|22|13521|doi:10.1002/chem.201601735
CCDC 1045718: Experimental Crystal Structure Determination
Related Article: Gong M. Chu, Israel Fernández, Andrés Guerrero-Martínez, Carmen Ramírez de Arellano and Miguel A. Sierra|2016|Eur.J.Inorg.Chem.||844|doi:10.1002/ejic.201501283
CCDC 1485045: Experimental Crystal Structure Determination
Related Article: Elena A. Giner, Alicia Santiago, Mar Gómez-Gallego, Carmen Ramírez de Arellano, Rebecca C. Poulten, Michael K. Whittlesey, and Miguel A. Sierra|2015|Inorg.Chem.|54|5450|doi:10.1021/acs.inorgchem.5b00492
CCDC 1045717: Experimental Crystal Structure Determination
Related Article: Gong M. Chu, Israel Fernández, Andrés Guerrero-Martínez, Carmen Ramírez de Arellano and Miguel A. Sierra|2016|Eur.J.Inorg.Chem.||844|doi:10.1002/ejic.201501283
CCDC 1440541: Experimental Crystal Structure Determination
Related Article: Miguel A. Sierra, Alba D. Merinero, Elena A. Giner, Mar Gómez-Gallego, Carmen Ramírez de Arellano|2016|Chem.-Eur.J.|22|13521|doi:10.1002/chem.201601735
CCDC 2012973: Experimental Crystal Structure Determination
Related Article: Alejandro Torres, Alba Collado, Mar Go��mez-Gallego, Carmen Rami��rez de Arellano, Miguel A. Sierra|2021|ACS Org. Inorg. Au|2|23|doi:10.1021/acsorginorgau.1c00011
CCDC 1960548: Experimental Crystal Structure Determination
Related Article: Sergio Aguado, Luis Casarrubios, Carmen Ramírez de Arellano, Miguel A. Sierra|2020|RSC Advances|10|29855|doi:10.1039/D0RA06002J
CCDC 1054408: Experimental Crystal Structure Determination
Related Article: Alexandra R. Rivero , Israel Fernández , Carmen Ramírez de Arellano , and Miguel A. Sierra|2015|J.Org.Chem.|80|1207|doi:10.1021/jo502292y
CCDC 1440540: Experimental Crystal Structure Determination
Related Article: Miguel A. Sierra, Alba D. Merinero, Elena A. Giner, Mar Gómez-Gallego, Carmen Ramírez de Arellano|2016|Chem.-Eur.J.|22|13521|doi:10.1002/chem.201601735
CCDC 952797: Experimental Crystal Structure Determination
Related Article: Marta Valencia, Mamen Martín-Ortiz, Mar Gómez-Gallego, Carmen Ramírez de Arellano, Miguel A. Sierra|2014|Chem.-Eur.J.|20|3831|doi:10.1002/chem.201304091
CCDC 1535717: Experimental Crystal Structure Determination
Related Article: Elena A. Giner, Mar Gómez-Gallego, Alba D. Merinero, Luis Casarrubios, Carmen Ramírez de Arellano, Miguel A. Sierra|2017|Chem.-Eur.J.|23|8941|doi:10.1002/chem.201701100
CCDC 1884097: Experimental Crystal Structure Determination
Related Article: Alba D. Merinero, Alba Collado, Luis Casarrubios, Mar Gómez-Gallego, Carmen Ramírez de Arellano, Antonio Caballero, Fabiola Zapata, Miguel A. Sierra|2019|Inorg.Chem.|58|16267|doi:10.1021/acs.inorgchem.9b02813
CCDC 1536882: Experimental Crystal Structure Determination
Related Article: Elena A. Giner, Mar Gómez-Gallego, Luis Casarrubios, María C. de la Torre, Carmen Ramírez de Arellano, Miguel A. Sierra|2017|Inorg.Chem.|56|2801|doi:10.1021/acs.inorgchem.6b02957
CCDC 952795: Experimental Crystal Structure Determination
Related Article: Marta Valencia, Mamen Martín-Ortiz, Mar Gómez-Gallego, Carmen Ramírez de Arellano, Miguel A. Sierra|2014|Chem.-Eur.J.|20|3831|doi:10.1002/chem.201304091
CCDC 1884096: Experimental Crystal Structure Determination
Related Article: Alba D. Merinero, Alba Collado, Luis Casarrubios, Mar Gómez-Gallego, Carmen Ramírez de Arellano, Antonio Caballero, Fabiola Zapata, Miguel A. Sierra|2019|Inorg.Chem.|58|16267|doi:10.1021/acs.inorgchem.9b02813
CCDC 952796: Experimental Crystal Structure Determination
Related Article: Marta Valencia, Mamen Martín-Ortiz, Mar Gómez-Gallego, Carmen Ramírez de Arellano, Miguel A. Sierra|2014|Chem.-Eur.J.|20|3831|doi:10.1002/chem.201304091
CCDC 1471182: Experimental Crystal Structure Determination
Related Article: Gong M. Chu, Andrés Guerrero-Martínez, Carmen Ramírez de Arellano, Israel Fernández, and Miguel A. Sierra|2016|Inorg.Chem.|55|2737|doi:10.1021/acs.inorgchem.5b02448
CCDC 1824868: Experimental Crystal Structure Determination
Related Article: María Frutos, Mar Gómez-Gallego, Elena A. Giner, Miguel A. Sierra, Carmen Ramírez de Arellano|2018|Dalton Trans.|47|9975|doi:10.1039/C8DT02296H
CCDC 1824870: Experimental Crystal Structure Determination
Related Article: María Frutos, Mar Gómez-Gallego, Elena A. Giner, Miguel A. Sierra, Carmen Ramírez de Arellano|2018|Dalton Trans.|47|9975|doi:10.1039/C8DT02296H
CCDC 1535716: Experimental Crystal Structure Determination
Related Article: Elena A. Giner, Mar Gómez-Gallego, Alba D. Merinero, Luis Casarrubios, Carmen Ramírez de Arellano, Miguel A. Sierra|2017|Chem.-Eur.J.|23|8941|doi:10.1002/chem.201701100
CCDC 1536881: Experimental Crystal Structure Determination
Related Article: Elena A. Giner, Mar Gómez-Gallego, Luis Casarrubios, María C. de la Torre, Carmen Ramírez de Arellano, Miguel A. Sierra|2017|Inorg.Chem.|56|2801|doi:10.1021/acs.inorgchem.6b02957
CCDC 1824869: Experimental Crystal Structure Determination
Related Article: María Frutos, Mar Gómez-Gallego, Elena A. Giner, Miguel A. Sierra, Carmen Ramírez de Arellano|2018|Dalton Trans.|47|9975|doi:10.1039/C8DT02296H
CCDC 952794: Experimental Crystal Structure Determination
Related Article: Marta Valencia, Mamen Martín-Ortiz, Mar Gómez-Gallego, Carmen Ramírez de Arellano, Miguel A. Sierra|2014|Chem.-Eur.J.|20|3831|doi:10.1002/chem.201304091