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Sanders VA, Cutler CS. Radioarsenic: A promising theragnostic candidate for nuclear medicine. Nucl Med Biol 2021; 92:184-201. [PMID: 32376084 DOI: 10.1016/j.nucmedbio.2020.03.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 03/18/2020] [Indexed: 10/24/2022]
Abstract
Molecular imaging is a non-invasive process that enables the visualization, characterization, and quantitation of biological processes at the molecular and cellular level. With the emergence of theragnostic agents to diagnose and treat disease for personalized medicine there is a growing need for matched pairs of isotopes. Matched pairs offer the unique opportunity to obtain patient specific information from SPECT or PET diagnostic studies to quantitate in vivo function or receptor density to inform and tailor therapeutic treatment. There are several isotopes of arsenic that have emissions suitable for either or both diagnostic imaging and radiotherapy. Their half-lives are long enough to pair them with peptides and antibodies which take longer to reach maximum uptake to facilitate improved patient pharmacokinetics and dosimetry then can be obtained with shorter lived radionuclides. Arsenic-72 even offers availability from a generator that can be shipped to remote sites and thus enhances availability. Arsenic has a long history as a diagnostic agent, but until recently has suffered from limited availability, lack of suitable chelators, and concerns about toxicity have inhibited its use in nuclear medicine. However, new production methods and novel chelators are coming online and the use of radioarsenic in the pico and nanomolar scale is well below the limits associated with toxicity. This manuscript will review the production routes, separation chemistry, radiolabeling techniques and in vitro/in vivo studies of three medically relevant isotopes of arsenic (arsenic-74, arsenic-72, and arsenic-77).
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Affiliation(s)
- Vanessa A Sanders
- Collider Accelerator Department, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Cathy S Cutler
- Collider Accelerator Department, Brookhaven National Laboratory, Upton, NY 11973, USA.
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Feng Y, DeGraffenreid AJ, Phipps MD, Rold TL, Okoye NC, Gallazzi FA, Barnes CL, Cutler CS, Ketring AR, Hoffman TJ, Jurisson SS. A trithiol bifunctional chelate for 72,77As: A matched pair theranostic complex with high in vivo stability. Nucl Med Biol 2018; 61:1-10. [DOI: 10.1016/j.nucmedbio.2018.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/13/2018] [Accepted: 03/04/2018] [Indexed: 12/21/2022]
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DeGraffenreid AJ, Feng Y, Barnes CL, Ketring AR, Cutler CS, Jurisson SS. Trithiols and their arsenic compounds for potential use in diagnostic and therapeutic radiopharmaceuticals. Nucl Med Biol 2016; 43:288-95. [PMID: 27150031 DOI: 10.1016/j.nucmedbio.2016.01.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 01/27/2016] [Accepted: 01/29/2016] [Indexed: 10/22/2022]
Abstract
INTRODUCTION Arsenic-72 ((72)As; 2.49MeV β(+), 26h) and (77)As (0.683MeV β(-), 38.8h) have nuclear properties useful for positron emission tomography (PET) and radiotherapy applications, respectively. Their half-lives are sufficiently long for targeting tumors with antibodies, as well as peptides. Potential radiopharmaceuticals based on radioarsenic require development of suitable bifunctional chelates for stable conjugation of arsenic to vectors under in vivo conditions at high dilution. METHODS The thiophilic nature of arsenic led to the synthesis and characterization of a simple trithiol ligand and its arsenic complex, and radiolabeling studies at the no carrier added (NCA) (77)As level. RESULTS (1)H- and (13)C-NMR spectroscopy, electrospray ionization mass spectrometry (ESI-MS), and single crystal X-ray diffraction were used to characterize the trithiol ligand and its arsenic(III) complex. Radiotracer studies with no carrier added (NCA) (77)As resulted in high radiolabeling yields (>96%) with high in vitro stability. CONCLUSIONS The high yield and stability of a single NCA (77)As trithiol complex indicates that this framework is suitable for developing matched pair agents for non-invasive in vivo PET imaging and radiotherapy of tumors with (72,77)As. This is the first reported chelate developed for NCA radioarsenic and studies are underway for developing a trithiol bifunctional chelate conjugated to a targeting vector, such as a peptide or monoclonal antibody.
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Affiliation(s)
| | - Yutian Feng
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA
| | - Charles L Barnes
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA
| | - Alan R Ketring
- Research Reactor Center (MURR), University of Missouri, Columbia, MO 65211, USA
| | - Cathy S Cutler
- Research Reactor Center (MURR), University of Missouri, Columbia, MO 65211, USA
| | - Silvia S Jurisson
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA; Research Reactor Center (MURR), University of Missouri, Columbia, MO 65211, USA.
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Photogeneration of hydrogen from water using CdSe nanocrystals demonstrating the importance of surface exchange. Proc Natl Acad Sci U S A 2013; 110:16716-23. [PMID: 24082134 DOI: 10.1073/pnas.1316755110] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Unique tripodal S-donor capping agents with an attached carboxylate are found to bind tightly to the surface of CdSe nanocrystals (NCs), making the latter water soluble. Unlike that in similarly solubilized CdSe NCs with one-sulfur or two-sulfur capping agents, dissociation from the NC surface is greatly reduced. The impact of this behavior is seen in the photochemical generation of H2 in which the CdSe NCs function as the light absorber with metal complexes in aqueous solution as the H2-forming catalyst and ascorbic acid as the electron donor source. This precious-metal-free system for H2 generation from water using [Co(bdt)2](-) (bdt, benzene-1,2-dithiolate) as the catalyst exhibits excellent activity with a quantum yield for H2 formation of 24% at 520 nm light and durability with >300,000 turnovers relative to catalyst in 60 h.
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Abd-El-Aziz AS, Strohm EA. Transition metal-containing macromolecules: En route to new functional materials. POLYMER 2012. [DOI: 10.1016/j.polymer.2012.08.024] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Abd‐El‐Aziz AS, Pilfold JL, Kucukkaya I, Vandel MS. Metal‐Containing Polymers. ENCYCLOPEDIA OF POLYMER SCIENCE AND TECHNOLOGY 2012. [DOI: 10.1002/0471440264.pst225.pub2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Abstract
The article provides an overview of the synthesis, properties, and applications of metal‐containing polymers. The past decade has shown an exponential increase in synthetic methods, resulting in metal‐containing polymers, their characterization techniques, and their potential application into a variety of fields, including chemistry, medicine, biotechnology, and more.
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Hofmann A, Schmiel P, Stein B, Graf C. Controlled formation of gold nanoparticle dimers using multivalent thiol ligands. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:15165-15175. [PMID: 22029627 DOI: 10.1021/la2028498] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Approaches for the controlled formation of gold nanoparticle dimers are investigated. These are based on a locally confined surface modification of gold nanoparticles followed by bridging two particles with an organic linker. A key factor in these approaches is the use of multivalent ligands. Citrate-stabilized gold nanoparticles are immobilized on a glass surface and mono- and multivalent thiol ligands are investigated regarding their ability to inactivate the nanoparticles sites facing away from the glass. A successful locally confined functionalization is only possible if multivalent ligands are used in this step. The application of monovalent ligands results in less stable particles without a permanent regioselective functionalization. This result can be explained by the dynamic equilibrium between bound and free ligands. Subsequently, the sites of the nanoparticles previously bound to the glass surface are functionalized with thiol ligands additionally bearing a reactive group. Approaches using dithiol linkers, diamine linkers, and coupling complementary functionalized particles are investigated. The highest yield of stable dimers is obtained from conditions where nanoparticles which are regioselectively functionalized with an N-hydroxysuccinimide ester are reacted with complementary amino-functionalized particles. The application of nanoparticles with activated carboxyl groups is essential since standard carboxyl activation agents induce an aggregation of the nanoparticles due to a reaction with remaining citrate molecules on the nanoparticle surface which reduces significantly electrostatic stabilization. This versatile approach using complementary regioselective with multivalent ligands functionalized nanoparticles may be also used for the coupling of particles with different size, shape, or composition, as well as a control of the interparticle distance.
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Affiliation(s)
- Andreas Hofmann
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany.
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Geier MJ, Vogels CM, Decken A, Westcott SA. Acetylacetonato(phosphane)iridium Complexes: Synthesis and Catalytic Activity in the Cyclization of Alkynoic Acids. Eur J Inorg Chem 2010. [DOI: 10.1002/ejic.201000655] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Affiliation(s)
- George R. Newkome
- Departments of Polymer Science and Chemistry, University of Akron, Akron, Ohio 44325-4717, and Department of Chemistry, Hiram College, Hiram, Ohio 44234
| | - Carol Shreiner
- Departments of Polymer Science and Chemistry, University of Akron, Akron, Ohio 44325-4717, and Department of Chemistry, Hiram College, Hiram, Ohio 44234
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Gregoli L, Danieli C, Barra AL, Neugebauer P, Pellegrino G, Poneti G, Sessoli R, Cornia A. Magnetostructural Correlations in Tetrairon(III) Single-Molecule Magnets. Chemistry 2009; 15:6456-67. [DOI: 10.1002/chem.200900483] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Danieli C, Cornia A, Cecchelli C, Sessoli R, Barra AL, Ponterini G, Zanfrognini B. A novel class of tetrairon(III) single-molecule magnets with graphene-binding groups. Polyhedron 2009. [DOI: 10.1016/j.poly.2008.12.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Troegel D, Walter T, Burschka C, Tacke R. Synthesis and Characterization of Tris(mercaptomethyl)(2,4,6-trimethoxyphenyl)silane and Its Use for the Immobilization of the Si(CH2SH)3 Group on Silica via an Si−O−Si Linkage. Organometallics 2009. [DOI: 10.1021/om8010118] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Dennis Troegel
- Universität Würzburg, Institut für Anorganische Chemie, Am Hubland, D-97074 Würzburg, Germany
| | - Tim Walter
- Universität Würzburg, Institut für Anorganische Chemie, Am Hubland, D-97074 Würzburg, Germany
| | - Christian Burschka
- Universität Würzburg, Institut für Anorganische Chemie, Am Hubland, D-97074 Würzburg, Germany
| | - Reinhold Tacke
- Universität Würzburg, Institut für Anorganische Chemie, Am Hubland, D-97074 Würzburg, Germany
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Angurell I, Rossell O, Seco M. Synthesis of Carbosilane Dendrimers Containing up to Four Metal Layers. Chemistry 2009; 15:2932-40. [DOI: 10.1002/chem.200802479] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Huang H, Rheingold AL, Hughes RP. Serendipitous Discovery of a Simple Compound with an Unsupported Ir−Ir Bond. Organometallics 2009. [DOI: 10.1021/om801110x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hui Huang
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of California, San Diego, California 92093-0358
| | - Arnold L. Rheingold
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of California, San Diego, California 92093-0358
| | - Russell P. Hughes
- Departments of Chemistry, 6128 Burke Laboratory, Dartmouth College, Hanover, New Hampshire 03755, and University of California, San Diego, California 92093-0358
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Huang H, Hurubeanu NR, Bourgeois CJ, Cheah SM, Yuan J, Rheingold AL, Hughes RP. Octahedral perfluoroalkyl complexes of Ir(III) formed by oxidative addition of perfluoroalkyl iodides to Ir(acac)(CO)2. CAN J CHEM 2009. [DOI: 10.1139/v08-114] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Oxidative addition of primary, secondary, or benzylic perfluoroalkyl iodides (RF–I) to the phosphine free Ir(I) precursor Ir(acac)(CO)2 1 (acac = 2,4-pentanedionato) proceeds smoothly to afford octahedral Ir(III) products Ir(acac)(I)(RF)(CO)2, A combination of X-ray crystallographic studies and solution spectroscopy shows that these products are the result of overall trans-addition of the C–I bond to iridium, probably a result of thermodynamic control; evidence for a kinetic product resulting from net cis-addition is obtained in one case. Treatment of the Ir(III) compounds with AgOTf (Tf = CF3SO3) illustrates that the iodo ligand is replaced by triflate with retention of stereochemistry at Ir. The resulting triflate complexes are inert to displacement by H2O or H2. The Ir(III) products exhibit very high CO stretching frequencies in the IR, indicating that the CO ligands may be non-classical. A quantitative estimation of the degree of backbonding to the CO ligands in these compounds, and a comparison of the π-acceptor properties of CO and fluoroalkyl ligands, is made using an approach based on Density Functional Theory (DFT) and Natural Bond Orbital analyses.Key words: iridium, fluoroalkyl, oxidation, carbonyl, DFT.
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Zhang W, Lalwani S, Chouai A, Simanek EE. Synthesis and Characterization of Anionic Triazine Dendrimers with a Labile Disulfide Core. Isr J Chem 2009; 49:23-30. [PMID: 19936277 PMCID: PMC2780346 DOI: 10.1560/ijc.49.1.23] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Anionic dendrimers based on melamine with disulfide bonds at the core were prepared to investigate the solubility of these architectures, the ability of these molecules to solubilize pyrene as a model drug, and the ability of these architectures to undergo thiol-disulfide exchange. The ability to solubilize pyrene is directly correlated with molecular weight of the dendrimer-aggregation of dendrons does not occur. Thiol-disulfide exchange occurs rapidly using dithiothreitol as the reductant to yield dendrimers with thiol cores that can undergo oxidation in air to yield the original dendrimer.
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Affiliation(s)
- Wen Zhang
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA
| | - Sanjiv Lalwani
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA
| | - Abdellatif Chouai
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA
| | - Eric E. Simanek
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA
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Rivas AB, Gascón JM, Lahoz FJ, Balana AI, Pardey AJ, Oro LA, Pérez-Torrente JJ. Synthesis, Structural Characterization, and Ligand Replacement Reactions of gem-Dithiolato-Bridged Rhodium and Iridium Complexes. Inorg Chem 2008; 47:6090-104. [DOI: 10.1021/ic800464p] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Angel B. Rivas
- Departamento de Química Inorgánica, Instituto Universitario de Catálisis Homogénea, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Centro de Equilibrios en Solución, Escuela de Química, Facultad de Ciencias, Universidad Central de Venezuela, Caracas, Venezuela
| | - José M. Gascón
- Departamento de Química Inorgánica, Instituto Universitario de Catálisis Homogénea, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Centro de Equilibrios en Solución, Escuela de Química, Facultad de Ciencias, Universidad Central de Venezuela, Caracas, Venezuela
| | - Fernando J. Lahoz
- Departamento de Química Inorgánica, Instituto Universitario de Catálisis Homogénea, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Centro de Equilibrios en Solución, Escuela de Química, Facultad de Ciencias, Universidad Central de Venezuela, Caracas, Venezuela
| | - Ana I. Balana
- Departamento de Química Inorgánica, Instituto Universitario de Catálisis Homogénea, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Centro de Equilibrios en Solución, Escuela de Química, Facultad de Ciencias, Universidad Central de Venezuela, Caracas, Venezuela
| | - Alvaro J. Pardey
- Departamento de Química Inorgánica, Instituto Universitario de Catálisis Homogénea, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Centro de Equilibrios en Solución, Escuela de Química, Facultad de Ciencias, Universidad Central de Venezuela, Caracas, Venezuela
| | - Luis A. Oro
- Departamento de Química Inorgánica, Instituto Universitario de Catálisis Homogénea, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Centro de Equilibrios en Solución, Escuela de Química, Facultad de Ciencias, Universidad Central de Venezuela, Caracas, Venezuela
| | - Jesús J. Pérez-Torrente
- Departamento de Química Inorgánica, Instituto Universitario de Catálisis Homogénea, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Centro de Equilibrios en Solución, Escuela de Química, Facultad de Ciencias, Universidad Central de Venezuela, Caracas, Venezuela
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Chen CH, Lin JT, Yeh MCP. Nonconjugated Red-Emitting Dendrimers with p-Type and/or n-Type Peripheries. Org Lett 2006; 8:2233-6. [PMID: 16706494 DOI: 10.1021/ol060493y] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] Dendron-encapsulated materials having a benzo[c][1,2,5]thiadiazole-based red-emitting core and p-type and/or n-type peripheries were synthesized. Intra- and intermolecular energy transfer from the peripheries to the core were found to be peripheries dependent. Red-emitting electroluminescent devices with promising performance were fabricated.
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Camerano JA, Casado MA, Ciriano MA, Oro LA. Tris(pyrazolyl)borate carbosilane dendrimers and metallodendrimers. Dalton Trans 2006:5287-93. [PMID: 17088968 DOI: 10.1039/b608558j] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A modified tris(pyrazolylborate) ligand has been prepared in two steps. First, reaction of triisopropylborate with allylmagnesium bromide and further treatment with benzoyl chloride gave CH(2) = CHCH(2)B(O(i)Pr), which was then reacted with potassium pyrazolate and pyrazole to give the compound K[CH(2) = CHCH(2)Bpz(3)]. The new allyl-containing scorpionate anion of acts as a bi- or tri-dentate ligand, as shown by the mononuclear complexes [CH(2) = CHCH(2)Bpz(3)M(LL)] (M = Rh, LL = nbd, ; LL = tfb, ; LL = (CO)(PPh(3)), ; M = Ir, LL = cod, ), obtained from reactions of the chlorido-bridged dinuclear complexes [{M(mu-Cl)(LL)}(2)] with 2. Furthermore, the borate represents a key material to achieve the attachment of tris(pyrazolyl)borate groups to the peripheries of carbosilane dendrimers. Thus, the platinum-catalyzed hydrosilylation reactions of compound with the dendritic cores Si[(CH(2))(3)SiMe(2)H](4) (G(0)-(SiH)(4)), (G(1)-(SiH)(8)), and (G(2)-(SiH)(16)) gave the corresponding borate-containing dendrimers Si[(CH(2))(3)SiMe(2)(CH(2))(3)B(O(i)Pr)(2)](4) (G(0)-B(4)), Si[(CH(2))(3)SiMe{(CH(2))(3)SiMe(2)(CH(2))(3)B(O(i)Pr)(2)}(2)](4) (G(1)-B(8)), and Si[(CH(2))(3)SiMe{(CH(2))(3)SiMe[(CH(2))(3)SiMe(2)(CH(2))(3)B(O(i)Pr)(2)](2)}(2)](4) (G(2)-B(16)) selectively in the anti-Markovnikov direction. Further reactions of G(0)-B(4), G(1)-B(8) and G(2)-B(16) with potassium pyrazolate and pyrazole rendered the corresponding polyanionic dendrimers K(4)[Si{(CH(2))(3)SiMe(2)(CH(2))(3)Bpz(3)}(4)] (G(0)-(Bpz(3))(4)), G(1)-(Bpz(3))(8), and G(2)-(Bpz(3))(16), respectively, which contain 4, 8, and 16 tris(pyrazolyl)borate groups symmetrically located around the dendritic peripheries. These unusual polyanionic dendrimers are excellent scaffolds to support metal centres, as shown by the reactions of G(0)-(Bpz(3))(4), G(1)-(Bpz(3))(8), and G(2)-(Bpz(3))(16) with [{Rh(mu-Cl)(nbd)}(2)] to give the neutral rhodadendrimers [Si{(CH(2))(3)SiMe(2)(CH(2))(3)Bpz(3)Rh(nbd)}(4)] G(0)-(Bpz(3)Rh)(4), G(1)-(Bpz(3)Rh)(8) and G(2)-(Bpz(3)Rh)(16) as stable solids in excellent yields. Following this protocol, mixed rhodium/iridium metallodendrimers can be prepared.
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Affiliation(s)
- José A Camerano
- Departamento de Química Inorgánica, Instituto de Ciencia de Materiales de Aragón, C.S.I.C.-Universidad de Zaragoza, E-50009 Zaragoza, Spain
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