Vincent J. Catalano

University of Nevada, Reno, Reno, Nevada, United States

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Publications (85)428.4 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The reaction of [Zn3 Cl3 L], in which L(3-) is a tris(β-diketiminate) cyclophane, with K(sBu)3 BH afforded [Zn3 (μ-H)3 L] (2), as confirmed by NMR spectroscopy, NOESY, and X-ray crystallography. The complex 2 was air-stable and unreactive towards water, methanol, and other substrates (e.g., nitriles) at room temperature over 24 h but reacted with CO2 (ca. 1 atm) to generate [Zn3 (μ-H)2 (μ-1,1-O2 CH)] (3). In contrast, [Zn3 (OH)3 L] (4) was found to be unreactive toward CO2 over the course of several days at 90 °C. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
    Angewandte Chemie International Edition 04/2015; DOI:10.1002/anie.201501539 · 11.34 Impact Factor
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    ABSTRACT: The reaction of [Zn3Cl3L], in which L3− is a tris(β-diketiminate) cyclophane, with K(sBu)3BH afforded [Zn3(μ-H)3L] (2), as confirmed by NMR spectroscopy, NOESY, and X-ray crystallography. The complex 2 was air-stable and unreactive towards water, methanol, and other substrates (e.g., nitriles) at room temperature over 24 h but reacted with CO2 (ca. 1 atm) to generate [Zn3(μ-H)2(μ-1,1-O2CH)] (3). In contrast, [Zn3(OH)3L] (4) was found to be unreactive toward CO2 over the course of several days at 90 °C.
    Angewandte Chemie 04/2015; DOI:10.1002/ange.201501539
  • Lyndsay B. Munro, Vincent J. Catalano
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    ABSTRACT: A series of 12 picolyl-containing NHC ligand precursors and their AgI salts are reported. The complexes [Ag3{Sim(CH2pyCl)2}3]X3 [2(PF6)3], [Ag3{Sim(CH2pyBr)2}3]X3 [3(PF6)3], [Ag3{Sim(CH2isoquin)2}3]X3 [4(PF6)3], [Ag3{5,6-Cl2-benzim(CH2py)2}3]X3 [6(BF4)3], [Ag3{5,6-Me2-benzim(CH2py)2}3]X3 [7(PF6)3], [Ag3(benzim{CH2py-3,4-(OMe)2}2)3]X3 [8(PF6)3], [Ag3{benzim(CH2py-3,5-Me2-4-OMe)2}3]X3 [9(PF6)3], [Ag3(5,6-Me2-benzim{CH2py-3,4-(OMe)2}2)3]X3 [10(PF6)3], [Ag3{5,6-Me2-benzim(CH2py-3,5-Me2-4-OMe)2}3]X3 [11(PF6)3], and [Ag3{5-OMe-benzim(CH2py)2}3]X3 [12(PF6)3] (X = PF6– or BF4–) each contain a central [Ag3]3+ core spanned by three NHC ligands. The optically pure [Ag3{(R,R)-cyclohexylim(CH2py)2}3](PF6)3 [(R,R)-5(PF6)3] adopts a different coordination mode. All complexes were characterized by NMR spectroscopy and HRMS. In addition, complexes 3(PF6), (R,R)-5(PF6), 6(BF4), 7(PF6), and 8(PF6) were characterized by single-crystal X-ray diffraction and found to exhibit Ag–Ag distances of approximately 2.7 Å.
    Berichte der deutschen chemischen Gesellschaft 10/2014; 2014(29). DOI:10.1002/ejic.201402483
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    ABSTRACT: Reactions between [Au(C6Cl2F3)(tht)] and P,N-donor bridging ligands of the type PPh2py and (PPh2)2phen lead to the homonuclear gold complexes [Au(C6Cl2F3)(PPh2py)] () and [Au2(C6Cl2F3)2{(PPh2)2phen}] (). Subsequent addition of [Cu(CH3CN)4](BF4) leads to the formation of the corresponding gold-copper heterometallic complexes [Au2Cu(C6Cl2F3)2(PPh2py)2](BF4) () and [Au2Cu(C6Cl2F3)2{(PPh2)2phen)}(CH3CN)](BF4) (). The four complexes have been structurally characterized and are luminescent. The gold precursors show emissions arising from metal-perturbed intraligand transitions. The heterometallic complexes show a red shift of the emissions that is proposed to arise from an admixture of IL (intraligand) and MLCT (metal-to-ligand-charge-transfer) transitions. DFT and TD-DFT calculations agree well with these results.
    Dalton Transactions 09/2014; 43(43). DOI:10.1039/c4dt02154a · 4.10 Impact Factor
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    ABSTRACT: In contrast to the wide number and variety of available synthetic routes to conventional linear polymers, the synthesis of two-dimensional polymers and unambiguous proof of their structure remains a challenge. Two-dimensional polymers-single-layered polymers that form a tiling network in exactly two dimensions-have potential for use in nanoporous membranes and other applications. Here, we report the preparation of a fluorinated hydrocarbon two-dimensional polymer that can be exfoliated into single sheets, and its characterization by high-resolution single-crystal X-ray diffraction analysis. The procedure involves three steps: preorganization in a lamellar crystal of a rigid monomer bearing three photoreactive arms, photopolymerization of the crystalline monomers by [4 + 4] cycloaddition, and isolation of individual two-dimensional polymer sheets. This polymer is a molecularly thin (~1 nm) material that combines precisely defined monodisperse pores of ~9 Å with a high pore density of 3.3 × 10(13) pores cm(-2). Atomic-resolution single-crystal X-ray structures of the monomer, an intermediate dimer and the final crystalline two-dimensional polymer were obtained and prove the single-crystal-to-single-crystal nature and molecular precision of the two-dimensional photopolymerization.
    Nature Chemistry 09/2014; 6(9):774-8. DOI:10.1038/nchem.2008 · 23.30 Impact Factor
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    ABSTRACT: An N,N-carbonyl-bridged dipyrrinone oxime has been synthesized and studied as a potential sensor for organophosphates. The molecular sensor underwent a drastic colorimetric response upon formation of the adduct. The pesticide dimethoate was found to produce the biggest spectral response, with a limit of detection equal to 4.0 ppm using UV-visible spectroscopy. Minimal fluorescence "turn on" via a PET mechanism was seen, and molecular modeling studies were used to explain the lower than expected PET response. The X-ray crystal structure of the fluorescent dipyrrinone oxime was also obtained.
    Organic Letters 05/2012; 14(11):2686-9. DOI:10.1021/ol300799f · 6.32 Impact Factor
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    ABSTRACT: The trigonally coordinated [AuCu(PPh(2)py)(3)](BF(4))(2) (1) crystallizes in two polymorphs and a pseudopolymorph, each of which contains a trigonally coordinated cation with short Au(I)-Cu(I) separations of ∼2.7 Å. Under UV illumination, these crystals luminesce different colors ranging from blue to yellow. The structures of these cations are nearly superimposable, and the primary difference resides in the relative placement of the anions and solvate molecules. As confirmed by time-dependent density functional theory calculations, it is these interactions that are responsible for the differential emission properties.
    Inorganic Chemistry 02/2012; 51(3):1207-9. DOI:10.1021/ic2023192 · 4.79 Impact Factor
  • Christoph E Strasser, Vincent J Catalano
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    ABSTRACT: The picolyl-substituted NHC complex [Au(im(CH(2)py)(2))(2)]PF(6) (1) reacts with two equivalents of copper(I) halides, affording compounds [Au(im(CH(2)py)(2))(2)(CuX)(2)]PF(6) (X = Cl, 2; Br, 3; I, 4). Each complex contains a nearly linearly coordinated [Au(NHC)(2)](+) center where the two picolyl groups on each im(CH(2)py)(2) ligand chelate a single copper atom. The Cu(I) center resides in a distorted tetrahedral environment and is coordinated to two pyridyl groups, a halide ion, and a gold metalloligand. The Au(I)-Cu(I) separations measure 2.7030(5), 2.6688(9), and 2.6786(10) Å for 2-4, respectively. Additionally, each Cu(I) center is further coordinated by a semibridging NHC ligand with short Cu-C separations of ~2.3 Å. In solution, these complexes dissociate the Cu(I) ion. In the solid state, 2-4 are photoluminescent with respective emission maxima of 512, 502, and 507 nm. The reaction of [Au(im(CH(2)py)(2))(2)]PF(6) with four equivalents of CuBr afforded the coordination polymer {[AuCu(2)Br(2)(im(CH(2)py)(2))(2)]Br·3CH(3)CN}(n) (5). This polymeric complex contains [Au(NHC)(2)](+) units interconnected by Cu(2)Br(2) dimers. In 5, the Au-Cu separations are long at 4.23 and 4.79 Å, while the Cu-Cu distance is considerably shorter at 2.9248(14) Å. In the solid state, 5 is photoluminescent with a broad band appearing at 533 nm.
    Inorganic Chemistry 11/2011; 50(21):11228-34. DOI:10.1021/ic201795b · 4.79 Impact Factor
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    ABSTRACT: A series of picolyl-substituted NHC-bridged triangular complexes of Ag(I) and Cu(I) were synthesized upon reaction of the corresponding ligand precursors, [Him(CH(2)py)(2)]BF4 (1a), [Him(CH(2)py-3,4-(OMe)(2))(2)]BF4 (1b), [Him(CH(2)py-3,5-Me-2-4-OMe)(2)]BF4 (1c), [Him(CH(2)py-6-COOMe)(2)]BF4 (1d), and [H(S)im(CH(2)py)(2)]-BF4 (1e), with Ag2O and Cu2O, respectively. Complexes [Cu-3(im(CH(2)py)(2))(3)](BF4)(3) (2a), [Cu-3(im(CH(2)py-3,4-(OMe)(2))(2))(3)](BF4)(3) (2b), [Cu-3(im(CH(2)py-3,5-Me-2-4-OMe)(2))(3)](BF4)(3), (2c), [Ag-3(im(CH(2)py-3,4-(OMe)(2))(2))(3)](BF4)(3), (3b), [Ag-3(im(CH(2)py-3,5-Me-2-4-OMe)(2))(3)](BF4)(3) (3c), [Ag-3(im(CH(2)py-6-COOMe)(2))(3)](BF4)(3) (3d), and [Ag-3((S)im(CH(2)py)(2))(3)](BF4)(3) (3e) were easily prepared by this method. Complex 2e, [Cu-3((S)im(CH(2)py)(2))(3)](BF4)(3), was synthesized by a carbene-transfer reaction of 3e, [Ag-3((S)im(CH(2)py)(2))(3)](BF4)(3), with CuCl in acetonitrile. The ligand precursor Id did not react with Cu2O. All complexes were fully characterized by NMR, UV-vis, and luminescence spectroscopies and high-resolution mass spectrometry. Complexes 2a-2c, 2e, and 3b-3e were additionally characterized by single-crystal X-ray diffraction. Each metal complex contains a nearly equilateral triangular M-3 core wrapped by three bridging NHC ligands. In 2a-2c and 2e, the Cu-Cu separations are short and range from 2.4907 to 2.5150 angstrom. In the corresponding Ag(I) system, the metal-metal separations range from 2.7226 to 2.8624 angstrom. The Cu(I)-containing species are intensely blue photoluminescent at room temperature both in solution and in the solid state. Upon UV excitation in CH3CN, complexes 2a-2c and 2e emit at 459, 427, 429, and 441 nm, whereas in the solid state, these bands move to 433, 429, 432, and 440 nm, respectively. As demonstrated by H-1 NMR spectroscopy, complexes 3b-3e are dynamic in solution and undergo a ligand dissociation process. Complexes 3b-3e are weakly photoemissive in the solid state.
    Inorganic Chemistry 08/2011; 50(17):8465-76. DOI:10.1021/ic201053t · 4.79 Impact Factor
  • Christoph E Strasser, Vincent J Catalano
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    ABSTRACT: Reaction of the Au(I) N-heterocyclic carbene (NHC) compound [Au(im(CH(2)py)(2))(2)]PF(6) with 2 equiv of [Cu(MeCN)(4)]PF(6) affords the tricationic compound [Au(im(CH(2)py)(2))(2)(Cu(MeCN)(2))(2)](PF(6))(3) (1), which exhibits blue luminescence (lambda(max) = 462 nm). Reaction of 1 with either liquid MeOH or MeOH vapor affords [Au(im(CH(2)py)(2))(2)(Cu(MeOH))(2)](PF(6))(3) (2), which produces green luminescence (lambda(max) = 520 nm) under UV excitation. The molecular structures of 1 x 2MeCN and 2 x 2MeOH.2Et(2)O were determined by single-crystal X-ray diffraction. Compound 1 contains a linearly coordinated [Au(NHC)(2)](+) core in which each picolyl side arm bridges a [Cu(MeCN)(2)](+) center. The Au...Cu separations are long at 4.596 A. Compound 2 exhibits two short Au...Cu interactions of 2.7195(7) A, with the Au(NHC)(2) core acting as an additional ligand toward each copper center to complete its tetrahedral coordination mode. Exposure of 2 to atmosphere produces a partial loss of MeOH accompanied by a luminescence color change to yellow (lambda(max) = 543 nm). The uptake and loss of MeOH vapor is rapid and reversible. Exposure of 2 to vacuum affords complete loss of MeOH, and the luminescence changes to yellow-orange (lambda(max) = 573 nm). Treatment of 2 with MeCN vapor regenerates 1. The interconversion of 1 and 2 was confirmed by powder X-ray diffraction. Compound 1 also reacts with acetone and H(2)O vapors, leading to species that produce yellow-orange (lambda(max) = 591 nm) and green (lambda(max) = 519 nm) emission, respectively. Compounds 1 and 2 are examples of molecular vapochromic materials that exhibit large changes in the emission though ligand substitution reactions between the solid complex and solvent vapors. The dramatic color change likely results from the "on-off" Au...Cu interactions induced by the ligand exchange reaction.
    Journal of the American Chemical Society 07/2010; 132(29):10009-11. DOI:10.1021/ja104585q · 11.44 Impact Factor
  • Vincent J Catalano, Adam L Moore, Jason Shearer, Jineun Kim
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    ABSTRACT: The coordination chemistry of copper(I) halides to the homoleptic, N-heterocyclic carbene Au(I) complexes [Au(CH(3)imCH(2)quin)(2)]BF(4) and Au(CH(3)imCH(2)py)(2)]BF(4) was explored. The reaction of CuX (X = Cl, Br, I) with either [Au(CH(3)imCH(2)quin)(2)]BF(4) or [Au(CH(3)imCH(2)py)(2)]BF(4) produces trimetallic complexes containing Cu(2)X(2)-butterfly copper clusters coordinated to the two imine moieties. The triangular arrangement of the metals places the gold(I) center in close proximity (approximately 2.5-2.6 A) to the centroid of the Cu-Cu vector. The Cu-Cu separations vary as a function of bridging halide with the shortest Cu-Cu separations of approximately 2.5 A found in the iodo-complexes and the longest separations of 2.9 A found in the bridging chloride complexes. In all six complexes the Au-Cu separations range from approximately 2.8 to 3.0 A. In the absence of halides, the dimetallic complex [AuCu(CH(3)imCH(2)py)(2)(NCCH(3))(2)](BF(4))(2), containing a long Au-Cu distance of approximately 4.72 A is formed. Additionally, as the byproduct of the reaction of CuBr with [Au(CH(3)imCH(2)quin)(2)]BF(4) the deep-red, dimetallic compound, AuCuBr(2)(CH(3)imCH(2)quin)(2), was isolated in very low yield. All of these complexes were studied by NMR spectroscopy, mass spectrometry, and the copper containing species were additionally characterized by X-ray crystallography. In solution the copper centers dissociate from the gold complexes, but as shown by XANES and EXAFS spectroscopy, at low temperature the Cu-Cu linkage is broken, and the individual copper(I) halides reposition themselves to opposite sides of the gold complex while remaining coordinated to one imine moiety. In the solid state all of the complexes are photoluminescent, though the nature of the excited state was not determined.
    Inorganic Chemistry 11/2009; 48(23):11362-75. DOI:10.1021/ic901914n · 4.79 Impact Factor
  • Amit K. Ghosh, Vincent J. Catalano
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    ABSTRACT: The reaction of [Au(CH3impy)2]PF6 (2), with substituted silver benzoate salts bearing different halide substituents produced a series of new mixed-metal species having two different structural motifs. One structural motif contains discrete tetrametallic Ag2Au2 diamond cores, whereas the other motif contains the same tetrametallic diamond core interconnected by benzoate-bridged silver dimers to form polymers. All the complexes are substitution-inert and stable both in the solid state as well as in solution. We also report the synthesis of oxidative addition products of [Au(CH3impy)2]PF6, which were also obtained during our attempts to oxidize the above-mentioned multimetallic assembly with bromine and iodine. Compounds 3–7 are intensely luminescent in frozen acetonitrile solution, but surprisingly no luminescence is observed at room temperature. All the complexes were completely characterized by 1H, 13C NMR, electronic absorption, emission spectroscopy, elemental analysis and X-ray crystallography. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
    Berichte der deutschen chemischen Gesellschaft 05/2009; 2009(13):1832 - 1843. DOI:10.1002/ejic.200801208
  • Guozhu Zhang, Vincent J. Catalano, Liming Zhang
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    ABSTRACT: ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
    ChemInform 01/2008; 39(4). DOI:10.1002/chin.200804115
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    ABSTRACT: We present our investigations of 2-ethyl-3-methyl-(10H)-dipyrrin-1-one, its self-association, and anion binding properties. This receptor is easily accessible in a facile single step synthesis with a straightforward workup. An examination of the concentration dependence of the dipyrrinone NH chemical shifts in CDCl3 and (CDCl2)2 over the temperature range from −20 °C to 100 °C determined the self-association constant to be 3850 M−1. Molecular recognition studies have shown that it has a preference for guests with an OH moiety, such as hydrogen sulfate (HSO4−) and carboxylic acids (RCO2H).Graphical abstract
    Tetrahedron 12/2007; 63(52):12994-12999. DOI:10.1016/j.tet.2007.10.033 · 2.82 Impact Factor
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    ABSTRACT: Starting from the Ru(bpp)Cl3 precursor (1), a family of novel heteroleptic RuII complexes of the general formulae [Ru(bpp)(dcbpyH)(X)] [X = Cl– (2a), NCS–, (3)] and Na[Ru(bpp)(dcbpy)(CN)] (4) with the ligands 2,6-bis(1-pyrazolyl)pyridine (bpp) and 2,2′-bipyridine-4,4′-dicarboxylic acid (dcbpyH2) has been synthesized, spectroscopically characterized, and attached to nanocrystalline TiO2 electrodes to be tested as solar cell sensitizers. Addition of HCl to (2a) led to the corresponding cationic derivative [Ru(bpp)(dcbpyH2)Cl]Cl (2b). All complexes were characterized by FT-IR, FT-Raman, UV/Vis, 1H NMR spectroscopy, elemental analysis, and mass spectrometry. Complex 4 and the previously reported [Ru(bdmpp)(dcbpyH2)Cl](PF6) (5) [bdmpp is 2,6-bis(3,5-dimethyl-1-pyrazolyl)pyridine] were characterized by single-crystal X-ray diffraction. The photo-electochemical properties of the dyes 2–4 were investigated and the efficiency of the corresponding dye-sensitized solar cells was compared to the sensitizing performance of the cis-[Ru(dcbpyH)2(NCS)2](NBu4)2 (N719) dye.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
    Berichte der deutschen chemischen Gesellschaft 12/2007; 2007(36):5633 - 5644. DOI:10.1002/ejic.200700287
  • Guozhu Zhang, Vincent J Catalano, Liming Zhang
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    ABSTRACT: A PtCl2-catalyzed 3,3-rearrangement/[3+2]-cycloaddition of propargylic 3-indoleacetates is developed. Besides the efficient formation of highly functionalized tetracyclic cyclopentenes, the reaction is dramatically divergent from that catalyzed by cationic Au-I. Moreover, the synthetic potential of this method is demonstrated by a succinct synthesis of the tetracyclic core of vindolinine.
    Journal of the American Chemical Society 10/2007; 129(37):11358-9. DOI:10.1021/ja074536x · 11.44 Impact Factor
  • Vincent J Catalano, Anthony O Etogo
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    ABSTRACT: Reaction of the imidazolium N-heterocyclic carbene precursor containing a methyl-substituted pyridyl functionality [HCH3im(CH3py)]PF6, 1, with Ag2O produces the homoleptic Ag(I) complex, [Ag(CH3im(CH3py))2]PF6, 2. In a simple carbene transfer reaction the analogous Au(I) species, [Au(CH3im(CH3py))2]PF6, 3, is formed by treatment of 2 with Au(tht)Cl in dichloromethane. Both 2 and 3 are structurally similar with nearly linearly coordinated NHC ligands. The methyl group appended to the pyridyl ring inhibits rotation of the pyridyl group at room temperature. Addition of AgBF4 to a hot propionitrile solution of 3 followed by crystallization with diethyl ether yields the one-dimensional coordination polymer, {[AuAg(CH3im(CH3py))2(NCCH2CH3)](BF4)2}n, 4, which contains Au-Ag separations of 2.9845(5) and 2.9641(5) A with intermetallic angles of 167.642(14) degrees and 162.081(9) degrees. This material is intensely luminescent in the solid state and exhibits an emission band at 453 nm (lambdaex=350 nm). Nearly colorless [Pd(CH3im(CH3py))2Cl]PF6, 5, is produced upon treatment of 2 with PdCl2(NCC6H5)2. The Pd(II) center in 5 is coordinated to one NHC ligand in a chelate fashion, while the second NHC is bound solely through the carbon center. The X-ray crystal structures of 1-5 are reported.
    Inorganic Chemistry 08/2007; 46(14):5608-15. DOI:10.1021/ic070260i · 4.79 Impact Factor
  • Liming Huang, Vincent J Catalano, Suk-Wah Tam-Chang
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    ABSTRACT: In this communication, we report the self-organization of a perylenedicarboximide to produce materials that exhibit dichroic (direction-dependent) absorption and anisotropic fluorescence emission of visible light.
    Chemical Communications 06/2007; DOI:10.1039/B615802A · 6.72 Impact Factor
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    ABSTRACT: HIV attachment via the CD4 receptor is an important target for developing novel approaches to HIV chemotherapy. Cyclotriazadisulfonamide (CADA) inhibits HIV at submicromolar levels by specifically down-modulating cell-surface and intracellular CD4. An effective five-step synthesis of CADA in 30% overall yield is reported. This synthesis has also been modified to produce more than 50 analogues. Many tail-group analogues have been made by removing the benzyl tail of CADA and replacing it with various alkyl, acyl, alkoxycarbonyl and aminocarbonyl substituents. A series of sidearm analogues, including two unsymmetrical compounds, have also been prepared by modifying the CADA synthesis, replacing the toluenesulfonyl sidearms with other sulfonyl groups. Testing 30 of these compounds in MT-4 cells shows a wide range of CD4 down-modulation potency, which correlates with ability to inhibit HIV-1. Three-dimensional quantitative structure-activity relationship (3D-QSAR) models were constructed using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) approaches. The X-ray crystal structures of four compounds, including CADA, show the same major conformation of the central 12-membered ring. The solid-state structure of CADA was energy minimized and used to generate the remaining 29 structures, which were similarly minimized and aligned to produce the 3D-QSAR models. Both models indicate that steric bulk of the tail group, and, to a lesser extent, the sidearms mainly determine CD4 down-modulation potency in this series of compounds.
    Journal of Medicinal Chemistry 03/2006; 49(4):1291-312. DOI:10.1021/jm0582524 · 5.48 Impact Factor
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    ABSTRACT: "Sterically geared" 9-(2,2,2-triphenylethylidene)fluorene (1) is of potential interest as a photoactive moiety in molecular devices, and the 2-tert-butyl derivative (6) has been synthesized to investigate photoisomerization. E and Z stereoisomers of 6 were separated and identified by X-ray crystallography. The tert-butyl group does not introduce additional strain, and its close proximity to the trityl group in the Z isomer suggests an attractive van der Waals interaction. The UV spectra of (E)-6 and (Z)-6 are nearly identical, showing absorption bands that are similar to those of fluorene occurring at wavelengths longer than 240 nm. Photoisomerization of 6 was investigated at 266, 280 and 320 nm. Solutions initially containing only (E)-6 or (Z)-6 were irradiated with pulsed laser light, monitoring isomerization by 1H NMR spectroscopy. Negligible photodecomposition was observed when the solutions were agitated by N2 ebullition. Experimental data were fitted to theoretical curves to obtain photoisomerization quantum yields (phi(ZE) and phi(EZ)) ranging from 0.04 to 0.09. This first photoisomerization study of a dibenzofulvene reveals significant quantum yields, despite theoretical prediction of inefficient or negligible isomerization of the parent hydrocarbon, fulvene. Thermal isomerization of 6 at 270 degrees C (t(1/2) = 120 min) was also followed by 1H NMR spectroscopy, resulting in an estimated activation energy (deltaG(double dagger)) of 43 kcal/mol.
    The Journal of Physical Chemistry A 01/2006; 109(51):11650-4. DOI:10.1021/jp054345l · 2.78 Impact Factor

Publication Stats

2k Citations
428.40 Total Impact Points

Institutions

  • 1995–2015
    • University of Nevada, Reno
      • Department of Chemistry
      Reno, Nevada, United States
  • 2002
    • Pasadena City College
      Pasadena, Texas, United States
  • 1997–2002
    • University of California, Davis
      • Department of Chemistry
      Davis, California, United States
    • Occidental College
      • Department of Chemistry
      Los Angeles, California, United States
  • 2000
    • University of Colorado at Boulder
      • Department of Chemistry and Biochemistry
      Boulder, Colorado, United States
  • 1996
    • Dalhousie University
      Halifax, Nova Scotia, Canada