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Ghiassian S, Ismaili H, Lubbock BDW, Dube JW, Ragogna PJ, Workentin MS. Photoinduced carbene generation from diazirine modified task specific phosphonium salts to prepare robust hydrophobic coatings. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:12326-12333. [PMID: 22839497 DOI: 10.1021/la301975u] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
3-Aryl-3-(trifluormethyl)diazirine functionalized highly fluorinated phosphonium salts (HFPS) were synthesized, characterized, and utilized as photoinduced carbene precursors for covalent attachment of the HFPS onto cotton/paper to impart hydrophobicity to these surfaces. Irradiation of cotton and paper, as proof of concept substrates, treated with the diazirine-HFPS leads to robust hydrophobic cotton and paper surfaces with antiwetting properties, whereas the corresponding control samples absorb water readily. The contact angles of water were determined to be 139° and 137° for cotton and paper, respectively. In contrast, water placed on the untreated or the control samples (those treated with the diazirine-HFPS but not irradiated) is simply absorbed into the surface. Additionaly, the chemically grafted hydrophobic coating showed high durability toward wash cycles and sonication in organic solvents. Because of the mode of activation to covalently tether the hydrophobic coating, it is amenable to photopatterning, which was demonstrated macroscopically.
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Magdzinski E, Gobbo P, Martin CD, Workentin MS, Ragogna PJ. The Syntheses and Electrochemical Studies of a Ferrocene Substituted Diiminopyridine Ligand and Its P, S, Se, and Te Complexes. Inorg Chem 2012; 51:8425-32. [DOI: 10.1021/ic300974u] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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53
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Snell KE, Ismaili H, Workentin MS. Photoactivated Nitrene Chemistry to Prepare Gold Nanoparticle Hybrids with Carbonaceous Materials. Chemphyschem 2012; 13:3185-93. [DOI: 10.1002/cphc.201200240] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Revised: 05/30/2012] [Indexed: 12/14/2022]
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54
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Khalili Najafabadi B, Hesari M, Workentin MS, Corrigan JF. New ferrocene based dithiolate ligands. J Organomet Chem 2012. [DOI: 10.1016/j.jorganchem.2011.12.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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55
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Hartlen KD, Ismaili H, Zhu J, Workentin MS. Michael addition reactions for the modification of gold nanoparticles facilitated by hyperbaric conditions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:864-871. [PMID: 22085199 DOI: 10.1021/la203662n] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The chemical interfacial modification of organic solvent soluble 2.4 ± 0.5 nm maleimide-modified monolayer protected gold nanoparticles (2-C(12)AuNPs) with primary or secondary amines via Michael addition reactions is demonstrated. Michael addition reactions between 2-C(12)AuNPs and primary or secondary amines at ambient temperature and pressure and under the conditions where the AuNP is soluble and stable are possible albeit sluggish, often taking days to weeks to go to completion. The rates and efficacies of the these same reactions are drastically increased at hyperbaric pressure conditions (11 000 atm) with no observed adverse effect to the gold nanoparticle stability. The resulting Michael addition adducts (3-C(12)AuNPs) formed from 2-C(12)AuNPs and the corresponding amines were characterized by TEM and by comparison of the (1)H NMR spectra of the 3-C(12)AuNPs with those of model reactions of the same amines with N-dodecylmaleimide, 2. The Michael addition reactions occur more readily with 2 rather than 2-C(12)AuNPs, consistent with the local environment of the latter imposing additional steric or other barriers to the reaction. The use of hyperbaric conditions makes the reaction of the organic solvent soluble 2-C(12)AuNP via Michael addition a viable interfacial modification process that is otherwise impractical. The results also suggest that it is a useful protocol for facilitating Michael addition reactions generally in solution at low temperatures.
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Gobbo P, Ghiassian S, Hesari M, Stamplecoskie KG, Kazemi-Zanjani N, Lagugné-Labarthet F, Workentin MS. Electrochemistry of robust gold nanoparticle–glassy carbon hybrids generated using a patternable photochemical approach. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm34984a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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57
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Ismaili H, Geng D, Sun AX, Kantzas TT, Workentin MS. Light-activated covalent formation of gold nanoparticle-graphene and gold nanoparticle-glass composites. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:13261-8. [PMID: 21928860 DOI: 10.1021/la202815g] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Monolayer protected gold nanoparticles (AuNPs) modified with a 3-aryl-3-(trifluoromethyl)diazirine functionality at its terminus (Diaz-AuNPs, 3.9 nm) were prepared and irradiated in the presence of two very different substrates, reduced graphene and glass. Upon irradiation, the terminal diazirine group loses nitrogen to generate a reactive carbene at the interface of the AuNPs that can then undergo addition or insertion reactions with functional groups on the graphene or glass surfaces, leading to the formation of graphene-AuNP and glass-AuNP hybrids, respectively. The AuNP hybrids were characterized using TEM, XRD, XPS, AFM, and UV-vis spectroscopy. Control experiments done in the absence of irradiation demonstrate that carbene activation is required for incorporation of significant AuNP onto the materials. The AuNP hybrids are robust and stable to excessive washing and centrifugation supporting the covalent nature of the interaction between the AuNP and the graphene or silicate glass substrates. Because the formation of the composite is light activated, it lends itself to photopatterning; this application is demonstrated for making the glass-AuNP composites.
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58
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Leigh WJ, Workentin MS. Tribute / Hommage. CAN J CHEM 2011. [DOI: 10.1139/v11-999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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59
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Leigh WJ, Workentin MS. Tribute / Hommage. CAN J CHEM 2011. [DOI: 10.1139/v11-900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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60
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Pitters JL, Adkinson DK, Griffiths K, Norton PR, Workentin MS. Chemoselective photochemical surface reaction — Ketene versus carbene reactivity from the photolysis of saturated monolayers of pyridyl diazoesters on single-crystal Pt. CAN J CHEM 2011. [DOI: 10.1139/v10-113] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Irradiation of saturated monolayers of 3- and 4-substituted pyridyl diazoacetates on single-crystal Pt surfaces leads to either the corresponding reactive carbene or stable ketene intermediate with the chemoselectivity determined by the position of the photoreactive substituent on the pyridyl ring, which ultimately directs the available interactions with neighboring substrates.
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61
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Ismaili H, Workentin MS. Covalent diamond–gold nanojewel hybrids via photochemically generated carbenes. Chem Commun (Camb) 2011; 47:7788-90. [DOI: 10.1039/c1cc12125a] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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62
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Ismaili H, Lee S, Workentin MS. Diazirine-modified gold nanoparticle: template for efficient photoinduced interfacial carbene insertion reactions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:14958-14964. [PMID: 20735050 DOI: 10.1021/la102621h] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Photolysis of a 3-aryl-3-(trifluoromethyl)diazirine-modified monolayer-protected gold nanoparticles (2-C(12)MPNs), with a core size of 1.8 ± 0.3 nm, in the presence of model carbene trapping reagents leads to efficient, essentially quantitative, modification of the interface via carbene insertion reactions. The utility of carbene insertion reactions as a general approach for the modification of Au-MPNs to provide a breadth of new structures available was demonstrated using acetic acid, methanol, benzyl alcohol, phenol, benzylamine, methyl acrylate, and styrene (10a-g, respectively) as electrophilic carbene trapping agents to form the corresponding modified 3a-g-C(12)MPNs. The 1.8 ± 0.3 nm gold nanoparticles bearing a diazirine group (2-C(12)MPNs) were synthesized using the ligand exchange reaction with the requisite 3-aryl-3-(trifluoromethyl)diazirinealkylthiol. The 2-C(12)MPNs and the resulting products of the reaction on the MPN (3a-g-C(12)MPN) were fully characterized by IR, (1)H NMR, and (19)F NMR spectroscopy and, when applicable, transmission electron microscopy (TEM). Verification for the 3a-g-C(12)MPNs was accomplished by comparison of the spectral data to those of obtained for the photoreactions of 3-(3-methoxyphenyl)-3-(trifluoromethyl)-3H-diazirine as a model with 10a-g.
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63
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Alizadeh A, Khodaei MM, Karami C, Workentin MS, Shamsipur M, Sadeghi M. Rapid and selective lead (II) colorimetric sensor based on azacrown ether-functionalized gold nanoparticles. NANOTECHNOLOGY 2010; 21:315503. [PMID: 20634571 DOI: 10.1088/0957-4484/21/31/315503] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A gold nanoparticle (AuNPs)-based simple and fast colorimetric sensor for selective detecting of Pb(II) in aqueous solution has been developed. Monodisperse AuNPs (approx. 2.0 nm diameter) has been prepared facilely and further modified with an alkanethiol-bearing monoazacrown ether terminus. These AuNPs are shown to selectively sense Pb(2+) through color change, which is visually discernible by an appearance of the surface plasmon band (SPB) at 520 nm. The recognition mechanism is attributed to the unique structure of the monoazacrown ether attached to AuNPs and metal sandwich coordination between two azacrown ether moieties that are attached to separate nanoparticles. This inter-particle cross-linking results in an aggregation and apparent color change from brown to purple. Additionally, TEM experiments support the optical absorption data proving the aggregation between azacrown ether-capped gold nanoparticles. This AuNP-based colorimetric assay is a facile and robust method and allows fast detection of Pb(2+) at ambient temperatures. More importantly, the developed technique does not utilize enzymatic reactions, light-sensitive dye molecules, lengthy protocols or sophisticated instrumentation.
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64
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Sauro VA, Magri DC, Pitters JL, Workentin MS. The electrochemical reduction of 1,4-dichloroazoethanes: Reductive elimination of chloride to form aryl azines. Electrochim Acta 2010. [DOI: 10.1016/j.electacta.2010.04.080] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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65
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Ismaili H, Alizadeh A, Snell KE, Workentin MS. Remarkable high-yielding chemical modification of gold nanoparticles using uncatalyzed click-type 1,3-dipolar cycloaddition chemistry and hyperbaric conditions. CAN J CHEM 2009. [DOI: 10.1139/v09-138] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Azide-terminated alkyl thiolate monolayer-protected gold nanoparticles (1-C12MPN) with a core size of 1.8 ± 0.2 nm were prepared. 1-C12MPN was modified in high yields via an uncatalyzed 1,3-dipolar cycloaddition (click-type reaction) with a variety of terminal acyl–alkynes under hyperbaric conditions at 11 000 atm. The resulting 1,2,3-triazole modified MPNs (2-C12MPN) were characterized using 1H NMR spectroscopy and were verified by comparison of the spectra to those obtained for the products of the model reactions of 1-azidododecane with the same alkynes. TEM analysis showed that the high-pressure conditions did not affect the size of the gold core, suggesting that the only effect is to facilitate the chemical reaction on the particles.
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66
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Zhu J, Lines BM, Ganton MD, Kerr MA, Workentin MS. Efficient Synthesis of Isoxazolidine-Tethered Monolayer-Protected Gold Nanoparticles (MPGNs) via 1,3-Dipolar Cycloadditions under High-Pressure Conditions. J Org Chem 2008; 73:1099-105. [DOI: 10.1021/jo702398r] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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67
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Magri DC, Workentin MS. A radical-anion chain mechanism following dissociative electron transfer reduction of the model prostaglandin endoperoxide, 1,4-diphenyl-2,3-dioxabicyclo[2.2.1]heptane. Org Biomol Chem 2008; 6:3354-61. [DOI: 10.1039/b809356c] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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68
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Shamsipur M, Kazemi SH, Alizadeh A, Mousavi MF, Workentin MS. Self-assembled monolayers of a hydroquinone-terminated alkanethiol onto gold surface. Interfacial electrochemistry and Michael-addition reaction with glutathione. J Electroanal Chem (Lausanne) 2007. [DOI: 10.1016/j.jelechem.2007.07.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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69
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Meneses AB, Antonello S, Arévalo MC, González CC, Sharma J, Wallette AN, Workentin MS, Maran F. Electron Transfer to Sulfides and Disulfides: Intrinsic Barriers and Relationship between Heterogeneous and Homogeneous Electron-Transfer Kinetics. Chemistry 2007; 13:7983-95. [PMID: 17616962 DOI: 10.1002/chem.200700382] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The electron-acceptor properties of series of related sulfides and disulfides were investigated in N,N-dimethylformamide with homogeneous (redox catalysis) and/or heterogeneous (cyclic voltammetry and convolution analysis) electrochemical techniques. The electron-transfer rate constants were determined as a function of the reaction free energy and the corresponding intrinsic barriers were determined. The dependence of relevant thermodynamic and kinetic parameters on substituents was assessed. The kinetic data were also analyzed in relation to corresponding data pertaining to reduction of diaryl disulfides. All investigated reductions take place by stepwise dissociative electron transfer (DET) which causes cleavage of the C(alkyl)--S or S--S bond. A generalized picture of how the intrinsic electron-transfer barrier depends on molecular features, ring substituents, and the presence of spacers between the frangible bond and aromatic groups was established. The reduction mechanism was found to undergo a progressive (and now predictable) transition between common stepwise DET and DET proceeding through formation of loose radical anions. The intrinsic barriers were compared with available results for ET to several classes of dissociative- and nondissociative-type acceptors, and this led to verification that the heterogeneous and the homogeneous data correlate as predicted by the Hush theory.
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70
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Zhu J, Ganton MD, Kerr MA, Workentin MS. Chemical modification of monolayer-protected gold nanoparticles using hyperbaric conditions. J Am Chem Soc 2007; 129:4904-5. [PMID: 17397169 DOI: 10.1021/ja070828m] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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71
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Najjar F, André-Barrès C, Baltas M, Lacaze-Dufaure C, Magri DC, Workentin MS, Tzédakis T. Electrochemical reduction of G3-factor endoperoxide and its methyl ether: evidence for a competition between concerted and stepwise dissociative electron transfer. Chemistry 2007; 13:1174-9. [PMID: 17066391 DOI: 10.1002/chem.200600445] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The reduction of the bicyclic G-factor endoperoxides G3 and G3Me was studied in N,N-dimethylformamide using cyclic voltammetry and convolution analysis. Electron transfer leads to irreversible cleavage of the O--O bond. Detailed analysis of the voltammetry curves reveals a non-linear dependence on the transfer coefficient indicating a mechanistic transition from a stepwise mechanism to one with more concerted character with increasing potential. By using quantum calculations to estimate the O--O bond dissociation energies, the experimental data was used to evaluate the standard reduction potentials and other pertinent thermochemical information.
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72
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Zhu J, Kell AJ, Workentin MS. A Retro-Diels−Alder Reaction to Uncover Maleimide-Modified Surfaces on Monolayer-Protected Nanoparticles for Reversible Covalent Assembly. Org Lett 2006; 8:4993-6. [PMID: 17048826 DOI: 10.1021/ol0615937] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Maleimide-modified monolayer-protected gold nanoparticles (MPGN) are prepared from the protected furan-maleimide via the thermally reversible Diels-Adler reaction when required. These maleimide-MPGNs serve as a general platform allowing for a Diels-Alder reaction with furan-modified MPN to prepare larger 3D networks reversibly. [reaction: see text]
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73
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Semenikhin OA, Hossain MMD, Workentin MS. Photoelectrochemistry of Conducting Polymers Modified with Electron-Acceptor Moieties. J Phys Chem B 2006; 110:20189-96. [PMID: 17034195 DOI: 10.1021/jp0631580] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The photoelectrochemical behavior of two polymers of the polythiophene series containing electron-acceptor groups in the main chain was studied and compared to that of the nonmodified polymer, poly(2,2'-bithiophene), PBT. The acceptor groups were 2,2'-bipyridine and biphenyl, which are electron-deficient as compared to the bithiophene unit. All three polymers demonstrated a pronounced photovoltaic effect, which for PBT was consistent with data reported earlier. The introduction of the electron-acceptor moieties was found to significantly enhance the magnitude of the steady-state photocurrent as well as to drastically alter the dependencies of the photocurrent on the polymer film thickness and the external bias. These observations indicated that the mechanism of photocurrent generation in the modified polymers differs from that in nonmodified polymer and involves the electron transfer to the electron-acceptor moieties in the polymer main chain. The values of the external quantum efficiency were estimated in a liquid-cell arrangement to be 0.27 and 0.19% for modified and nonmodified polymers, respectively.
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74
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Nematollahi D, Workentin MS, Tammari E. Electrochemical oxidation of catechol in the presence of cyclopentadiene. Investigation of electrochemically induced Diels–Alder reactions. Chem Commun (Camb) 2006:1631-3. [PMID: 16583002 DOI: 10.1039/b516814g] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We describe the synthesis and kinetic evaluation of compounds from [4 + 2] alone and [4 + 2] followed by [2 + 2] cycloaddition reactions of electrochemically generated o-benzoquinone with 1,3-cyclopentadiene.
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75
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Kell AJ, Alizadeh A, Yang L, Workentin MS. Monolayer-protected gold nanoparticle coalescence induced by photogenerated radicals. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:9741-6. [PMID: 16207061 DOI: 10.1021/la051655m] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Acyl and alkyl radicals generated photochemically in a solution containing monolayer-protected gold nanoparticles are shown to efficiently liberate the alkylthiolate ligands into the solution as the thioacetyl or alkyl sulfide, respectively. This radical-induced reaction initiates a coalescence of the gold cores to facilitate an increase in core size. The photoinitiated radical reaction also liberates monolayers from two-dimensional gold surfaces.
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