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John P Fackler

Publications and source records attributed to John P Fackler.

18 recordsLinked to original sources
PubMed2007

Syntheses of mixed-ligand tetranuclear gold(I)-nitrogen clusters by ligand exchange reactions with the dinuclear gold(I) formamidinate complex Au(2)(2,6-Me2Ph-form)2.

The reaction of the sterically crowded dinuclear gold(I) amidinate complex Au2(2,6-Me2Ph-form)2, 1, with the less bulky bidentate nitrogen ligands results in the formation of tetranuclear gold(I) complexes. When the less bulky amidinate, K(4-MePh-form), A, was reacted with 1 in a 1:1 stoichiometric ratio, crystals containing equal amounts of the tetranuclear and dinuclear gold(I) aryl formamidinates, Au4(4-MePh-form)4 and Au2(2,6-Me2Ph-form)2, where 2,6-Me2Ph-form = B, were found in the same unit cell, 2 x 2THF: space group P, a = 10.794(11) A, b = 14.392(15) A, c = 25.75(3) A, alpha = 82.564(17) degrees, beta = 85.443(18) degrees, gamma = 82.614(19) degrees. The reaction of K(4-MePh-form), A, and 1 in a 1:2 ratio (excess) produced the tetranuclear complex only, 3. The potassium salt of the exchanged bulky ligand, K(2,6-Me2Ph-form), formed as a byproduct. The reaction of the dinuclear gold(I) complex Au2(2,6-Me2Ph-form)2 with the 3,5-diphenylpyrazolate salt, K(3,5-Ph2pz), resulted in the formation of two tetranuclear mixed-ligand complexes, Au4(3,5-Ph2pz)2(2,6-Me2Ph-form)2 x 2THF, 4 x 2THF (space group P21/c, a = 11.5747(19) A, b = 25.497(4) A, c = 21.221(3) A, beta = 96.979(3) degrees) and Au4(3,5-Ph2pz)3(2,6-Me2Ph-form) x THF, 5 x THF (space group P21/c, a = 23.058(5) A, b = 14.314(3) A, c = 18.528(4) A, beta = 90.94(3) degrees. The block crystals from the tetranuclear complex, 4 x 2THF, contain mixed ligands with each pyrazolate ring facing an amidinate ring. The tetranuclear mixed ligand complex, 5 x THF, was isolated as needles with ligands alternating above and below the Au4 plane. The two tetranuclear mixed-ligand complexes emit at 490 and 530 nm, respectively, under UV excitation.

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PubMed2006

Gold(I) and silver(I) mixed-metal trinuclear complexes: dimeric products from the reaction of gold(I) carbeniates or benzylimidazolates with silver(I) 3,5-diphenylpyrazolate.

Trinuclear mixed-metal gold-silver compounds are obtained by the reaction of gold(I) carbeniate [Au(mu-C(OEt)=NC6H4-p-CH3)]3, TR(carb), or gold(I) imidazolate [Au-mu-C,N-1-benzyl-2-imidazolate]3, TR(bzim), with silver(I) pyrazolate [Ag(mu-3,5-Ph2pz)]3. The crystalline products are mixed-ligand, mixed-metal dimeric products [Au(carb)Ag2(mu-3,5-Ph2pz)2], [Au2(carb)2Ag(mu-3,5-Ph2pz)].CH2Cl2, [Au(bzim)2Ag2(mu-3,5-Ph2pz)], and [Au2(bzim)2Ag(mu-3,5-Ph2pz)]. They have been characterized by elemental analysis and 1H NMR and mass spectrometry. The X-ray structure of [Au(carb)Ag2(mu-3,5-Ph2pz)2] shows it to be a dimer with two Ag...Au contacts between the trinuclear units of 3.083(2) and 3.310(2) A and with average intramolecular Ag...Ag and Au...Ag distances of approximately 3.3 and 3.2 A, respectively. The structure of [Au2(carb)2Ag(mu-3,5-Ph2pz)].CH2Cl2 is a dimer with one intermolecular Au...Au attraction of 3.3354(10) A and a short Ag...Au distance of approximately 3.42 A and intramolecular Ag...Au and Au...Au contacts of approximately 3.2 and approximately 3.3 A, respectively. Packing diagrams of both complexes show that the dimeric units are independent, similar to their parent molecules. The dimers of trinuclear [Au(carb)Ag2(mu-3,5-Ph2pz)2] and [Au2(carb)2Ag(mu-3,5-Ph2pz)].CH2Cl2 crystallize in the triclinic space group P (Z = 2), a = 9.688(3) A, b = 15.542(4) A, c = 23.689(6) A, alpha = 82.560(5) degrees , beta = 87.887(6) degrees , gamma = 78.060(5) degrees , and the orthorhombic space group Pca2(1) (Z = 4), a = 29.644(4) A, b = 7.4582(10) A, c = 30.473(4) A, respectively. The structure of [Au(bzim)Ag2(mu-3,5-Ph2pz)2] is a dimer with two metallophilic Ag...Au interactions of 3.14 A. The complex crystallizes in the monoclinic space group C2/c (Z = 4), a = 26.368(5) A, b = 15.672(3) A, c = 17.010(3) A, beta = 102.206(3) degrees .

Crystallography, X-Ray↗
PubMed2006

Mercury(II) cyanide coordination polymer with dinuclear gold(I) amidinate. Structure of the 2-D [Au2(2,6-Me2-formamidinate)2].2Hg(CN)2.2THF complex.

The dinuclear gold(I) amidinate complex [Au(2)(Me(2)-form)(2)], 1, (Me(2)-form = 2,6-Me(2)-formamidinate) reacts with Hg(CN)(2) to form a 2D structure, 1.2Hg(CN)(2).2THF. Each gold center interacts with two Hg(CN)(2) molecules. The Au...Au distance increases from 2.7 Angstroms in the starting dinuclear complex to 2.9 Angstroms in the adduct. The gold centers are connected to four nitrogen atoms with Au-N distances in the range 2.13-2.51 Angstroms. The cyanide stretch is shifted from 2192 cm(-1) in the Hg(CN)(2) to 2147 cm(-1) in the adduct.

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PubMed2005

External heavy-atom effect of gold in a supramolecular acid-base pi stack.

The nucleophilic trinuclear Au(I) ring complex Au3(p-tolN=COEt)3, 1, forms a sandwich adduct with the organic Lewis acid octafluoronaphthalene, C10F8. The 1.C10F8 adduct has a supramolecular structure consisting of columnar interleaved 1 ratio 1 stacks in which the Au3(p-tolN=COEt)3 pi-base molecules alternate with the octafluoronaphthalene pi-acid molecules with distances between the centroid of octafluoronaphthalene to the centroid of 1 of 3.458 and 3.509 A. The stacking with octafluoronaphthalene completely quenches the blue photoluminescence of Au3 (p-tolN=COEt)3, which is related to inter-ring Au-Au bonding, and leads to the appearance of a bright yellow emission band observed at room temperature. The structured profile, the energy, and the lifetime indicate that the yellow emission of the 1.C10F(8) adduct is due to monomer phosphorescence of the octafluoronaphthalene. The 3.5 ms lifetime of the yellow emission of 1.C10F8 is two orders of magnitude shorter than the lifetime of the octafluoronaphthalene phosphorescence, thus indicating a strong gold heavy-atom effect. The diffuse-reflectance spectrum of the solid adduct shows new absorptions that are red-shifted from the absorptions of the monomeric organic and inorganic components alone, indicating charge transfer. Luminescence excitation spectra suggest that these new absorptions represent the major excitation route that leads to the yellow luminescence of 1.C10F8, which is different from the conventional heavy-atom effect in which the phosphorescence route entails simply the enhancement of the S1-T1 intersystem crossing of the organic compound.

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PubMed2005

The role of F-centers in catalysis by Au supported on MgO.

A correlation is found between the activity of Au clusters for the catalytic oxidation of CO and the concentration of F-centers in the surface of a MgO support. These results are consistent with recent theoretical results showing that F-centers in MgO serve to anchor Au clusters and control their charge state by partial transfer of charge from the substrate F-center to the Au cluster.

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PubMed2005

Novel metallamacrocyclic gold(I) thiolate cluster complex: structure and luminescence of [Au9(mu-dppm)4(mu-p-tc)6](PF6)3.

The structure of a novel metallamacrocyclic phosphine gold(I) thiolate cluster, [Au9(mu-dppm)4(mu-p-tc)6](PF6)3, where dppm = bis(diphenylphosphine)methane and p-tc = p-thiocresolate, is reported and shows AuAu attractions of approximately 3.0 A and gold(I) atoms linked to thiolate and phosphine ligands in distorted trigonal and nearly linear geometries.

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PubMed2005

Synthesis and X-ray structures of dinuclear and trinuclear gold(I) and dinuclear gold(II) amidinate complexes.

The structures of the trinuclear gold(I), [Au(3)(2,6-Me(2)-form)(2)-(THT)Cl], the dinuclear [Au(2)(2,6-Me(2)-form)(2)], and the oxidative-addition product [Au(2)(2,6-Me(2)-form)(2)Cl(2)] formamidinate complexes are reported. The trinuclear complex is stable with gold-gold distances 3.01 and 3.55 A. The gold-gold distance in the dinuclear complex decreases upon oxidative-addition with halogens from 2.7 to 2.5 A, similar to observations made with the dithiolates and ylides.

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PubMed2004

Synthesis, characterization, and luminescent properties of dinuclear gold(I) xanthate complexes: X-ray structure of [Au2(nBu-xanthate)2].

The synthesis and characterization of gold(I) complexes of butyl xanthate [Au(2)((n)()Bu-xanthate)(2)], 1, and ethyl xanthate [Au(2)(Et-xanthate)(2)], 2, are described. These complexes are readily prepared from the reaction between Au(THT)Cl (THT = tetrahydrothiophene) and the corresponding xanthate ligands as the potassium salts. The two xanthate complexes are characterized by (1)H NMR, IR, mass spectrometry, elemental analysis, and UV-vis techniques. Thermal gravimetric analysis (TGA) and differential thermal analysis (DTA) show that the gold xanthate complexes decompose to yield mainly gold metal at approximately 200 degrees C, confirmed by X-ray powder diffraction. Excitation of the complexes at 450 nm in the solid state at 77 K produces a strong red emission at ca. 690 nm with a broad asymmetric profile tailing to 850 nm. The dinuclear gold(I) xanthate complex, [Au(2)(nBu-xanthate)(2)], 1, is the first structurally characterized binary Au(I) xanthate. The Au...Au distance in the eight-membered ring is 2.8494(15) A while the shortest intermolecular Au...Au interaction between independent units is 3.64 A. The angle between the planes containing the molecules in the unit cell is approximately 69.56 degrees. The light green plates of [Au(mu-S(2)COBu(n))](2) crystallize in the orthorhombic space group P2(1)2(1)2 with a = 37.254(14) A, b = 7.287(3) A, c = 6.054(2) A, alpha = beta = gamma = 90 degrees, Z = 4, and V = 1643.4(11) A(3).

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PubMed2004

A detailed study of the vapochromic Behavior of [Tl[Au(C6Cl5)2]]n.

The linear-chain polymer [Tl[Au(C(6)Cl(5))(2)]](n), 1, reacts in the solid state and in solution with different volatile organic compounds such as tetrahydrofuran, acetone, tetrahydrothiophene, 2-fluoropyridine, acetonitrile, acetylacetone, and pyridine. Solid-state exposure of 1 to vapors of the above VOCs produces a selective and reversible change in its color that is perceptible to the human eye and even deeper under UV irradiation, allowing 1 to function as a sensor for these VOCs. Heating the samples exposed to the VOCs for a few minutes at 100 degrees C regenerates the original material without degradation, even after several exposure/heating cycles. The reversibility is further confirmed by X-ray powder diffraction measurements of complex 1 before and after exposure to vapors and again after heating the samples. The products obtained by reactions of complex 1 with the above VOCs as ligands in solution contain extended linear chains of alternating gold and thallium centers with two molecules of the organic ligands attached to each thallium atom. The stoichiometry of these materials has been confirmed by single-crystal X-ray diffraction as [Tl(THF)(2)[Au(C(6)Cl(5))(2)]](n), 3, and [Tl(acacH)(2)[Au(C(6)Cl(5))(2)]](n), 5. Comparison of FT-IR, UV-vis, and luminescence spectra at room temperature and at 77 K of the solid samples of complexes 2-9 with the spectra of complex 1 after its exposure to VOCs suggests interaction occurs between the organic VOCs and thallium in each case. Thermogravimetric analyses data indicate that all the thallium centers in these derivatives of complex 1 are neither fully nor equally coordinatively saturated. The materials formed appear to be intermediates between complex 1 with no VOCs attached and complexes 3-9 which contain two organic ligands coordinated to each thallium. A crystal structure analyses of one of these intermediates, [Tl(THF)(0.5)[Au(C(6)Cl(5))(2)]](n), 1.0.5THF, confirms this. Density functional calculations are in accord with the observed experimental results. Analysis reveals a substantial participation of the metal atoms in transitions that give rise to the observed emissions. Crystallographic data are as follows. For 1.0.5THF: triclinic, P1, a = 8.9296(1) A, b = 11.2457(1) A, c = 21.2465(3) A, alpha = 96.7187(7) degrees, beta = 92.5886(6) degrees, gamma = 98.5911(8) degrees, V = 2090.87(4) A(3), and Z = 2. For 3: monoclinic, P2(1)/c, a = 26.4163(6) A, b = 12.1619(2) A, c = 28.0813(6) A, alpha = 90 degrees, beta = 161.9823(6) degrees, gamma = 90 degrees, V = 2790.51(10) A(3), and Z = 4. For 5: monoclinic, P2(1)/c, a = 9.8654(2) A, b = 29.8570(5) A, c = 11.6067(2) A, alpha = 90 degrees, beta = 114.5931(6) degrees, gamma = 90 degrees, V = 3108.64(10) A(3), and Z = 4.

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PubMed2003

Syntheses and structures of dinuclear gold(I) dithiophosphonate complexes and the reaction of the dithiophosphonate complexes with phosphines: diverse coordination types.

The dinuclear gold(I) dithiophosphonate complex, [Au(2)(dtp)(2)] (1), where dtp = [S(2)P(R)(OR')](-) with R = p-C(6)H(4)OCH(3); R'= c-C(5)H(9), has been synthesized and its reaction studied with the phosphine ligands PPh(3) and Ph(2)P(CH(2))(n)PPh(2) (n = 1-4). Compound 1 contains two gold atoms homobridged by the anionic dithiophosphonate ligand, forming an eight-membered ring complex in a chair form. After the reaction of 1 with diphosphine ligands, the dinuclear open-ring complexes Au(2)(dppm)(dtp)(2) (2), Au(2)(dppe)(dtp)(2) (3), Au(2)(dppp)(dtp)(2) (4), Au(2)(dppb)(dtp)(2) (5) were formed (dppm = diphenylphosphinomethane; dppe = diphenylphosphinoethane; dppp = diphenylphosphinopropane; dppb = diphenylphosphinobutane). The reaction with dppm is stoichiometry-dependent. Thus, when 1 reacts with 2 equiv of dppm, the ionic complex [Au(2)(dppm)(2)(dtp)]dtp forms. This dtp counterion was exchanged with tetrafluoroborate to yield [Au(2)(dppm)(2)(dtp)]BF(4), the crystallization of which afforded two interconvertible isomers, 6-yellow and 7-white. Reaction of 1 with PPh(3) affords the tetracoordinate mononuclear complex [Au(dtp)(PPh(3))(2)] (8). The molecular structures of 1-8 were confirmed by X-ray crystallography and show multiple coordination modes and geometries. The crystal structures of 1 and its reaction products with dppm (2, 6, 7) show short intramolecular Au.Au aurophilic bonding interactions of 2.95-3.10 A while no intermolecular interactions were discernible. However, reaction products of 1 with longer-chain Ph(2)P(CH(2))(n)PPh(2) ligands, n = 2-4, exhibit structures that lack both intra- and intermolecular Au.Au interactions.

Crystallography, X-Ray↗
PubMed2003

(Tl[Au(C(6)Cl(5))(2)])(n): A vapochromic complex.

The X-ray structure of (Tl[Au(C(6)Cl(5))(2)])(n), 1, consists of 1-D linear polymer chains parallel to the crystallographic z axis. The crystal structure of 1 has channels that run parallel to these chains with interatom distances in the range 3.231-4.076 A. There are holes in these channels with diameters as large as 10.471 A, which can accommodate a variety of solvents. Complex 1 displays reversible vapochromic emission and absorption spectral behavior when the solid is exposed to a variety of organic vapors such as acetone, acetonitrile, triethylamine, acetylacetone, tetrahydrothiophene, 2-fluoropyridine, tetrahydrofuran, and pyridine. Complex 1 is luminescent at room temperature and at 77 K in the solid state. UV excitation at 495 nm leads to an emission at 531 nm.

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PubMed2002

Forty-five years of chemical discovery including a golden quarter-century.

Inorganic chemistry became a passion for me as a graduate student in the 1950s. It was exciting to be part of the renaissance of the discipline, and I am pleased to have contributed to its strength. Physical concepts applied to the understanding of the properties of transition metal compounds guided our work initially. In the 1970s, probably as a direct result of the world abandoning the gold standard, the chemistry of gold was awakened after a long sleep. Much of the chemistry covered in this review of our work relates to novel compounds of gold and the properties they display which have been uncovered during the last 25 years of the 20th century. Stable metal-metal bonded Au(II) and organometallic Au(III) compounds, bi- and trimetallic oxidative addition, phosphorescent species with microsecond lifetimes, gold chains resulting from aurophilic bonding stronger than H-bonding, and recently, gold binding to organic pi acids have intrigued my group and other gold chemists during this period.

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PubMed2002

Syntheses, structure, and photoluminescence properties of the 1-dimensional chain compounds [(TPA)(2)Au][Au(CN)(2)] and (TPA)AuCl (TPA = 1,3,5-triaza-7-phosphaadamantane).

The structures and temperature-dependent photoluminescence properties of the one-dimensional compounds [(TPA)(2)Au][Au(CN)(2)], 1, and (TPA)AuCl, 2, are reported. An extended linear chain with weak Au.Au interactions along the c-axis is evident in the structure of 1, and a helical chain with a pitch of 3.271 A is seen for 2. The intrachain Au...Au separation is 3.457(1) and 3.396(2) A in 1 and 2, respectively. As a result of this weak Au...Au interaction, the physical properties of these compounds are anisotropic. Scanning electron microscopy (SEM) studies indicate that single crystals of both compounds are noninsulating. Single crystals of 1 do not luminesce visibly, but grinding the crystals finely initiates a strong green emission under UV irradiation at room temperature. Further interesting optical properties include the dependence of the emission profile of the powder on the exciting wavelength and luminescence thermochromism. When excited at wavelengths < 360 nm, the powder exhibits a blue emission at 425 nm while excitation with longer wavelengths leads to a green emission near 500 nm. While the green emission dominates at ambient temperature, cooling to cryogenic temperatures leads to the dominance of the blue emission. Fibers of 2 are luminescent at 78 K with an emission band centered at 580 nm. Compound 1 crystallizes in the orthorhombic space group Cccm (No. 66), with Z = 2, a = 6.011(1) A, b = 23.877(6) A, c = 6.914(1) A, V = 992.3(3) A(3), and R = 0.0337. Compound 2 crystallizes in the trigonal space group R3 (No. 148), with Z = 18, a = 22.587(2) A, b = 22.587(2) A, c = 9.814(2) A, V = 4336 A(3), and R = 0.0283.

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PubMed2002

Dinuclear gold(I) dithiophosphonate complexes: synthesis, luminescent properties, and X-ray crystal structures of [AuS(2)PR(OR')](2) (R = Ph, R' = C(5)H(9); R = 4-C(6)H(4)OMe, R' = (1S,5R,2S)-(--)-menthyl; R = Fc, R' = (CH(2))(2)O(CH(2))(2)OMe).

2,4-Diaryl- and 2,4-diferrocenyl-1,3-dithiadiphosphetane disulfide dimers (RP(S)S)(2) (R = Ph (1a), 4-C(6)H(4)OMe (1b), FeC(10)H(9) (Fc) (1c)) react with a variety of alcohols, silanols, and trialkylsilyl alcohols to form new dithiophosphonic acids in a facile manner. Their corresponding salts react with chlorogold(I) complexes in THF to produce dinuclear gold(I) dithiophosphonate complexes of the type [AuS(2)PR(OR')](2) in satisfactory yield. The asymmetrical nature of the ligands allows for the gold complexes to form two isomers (cis and trans) as verified by solution (1)H and (31)P[(1)H] NMR studies. The X-ray crystal structures of [AuS(2)PR(OR')](2) (R = Ph, R' = C(5)H(9) (2); R = 4-C(6)H(4)OMe, R' = (1S,5R,2S)-(-)-menthyl (3); R = Fc, R' = (CH(2))(2)O(CH(2))(2)OMe (4)) have been determined. In all cases only the trans isomer is obtained, consistent with solid state (31)P NMR data obtained for the bulk powder of 3. Crystallographic data for 2 (213 K): orthorhombic, Ibam, a = 12.434(5) A, b = 19.029(9) A, c = 11.760(4) A, V = 2782(2) A(3), Z = 4. Data for 3 (293 K): monoclinic, P2(1), a = 7.288(2) A, b = 12.676(3) A, c = 21.826(4) A, beta = 92.04(3) degrees, V = 2015.0(7) A(3), Z = 2. Data for 4 (213 K): monoclinic, P2(1)/n, a = 11.8564(7) A, b = 22.483(1) A, c = 27.840(2) A, beta = 91.121(1) degrees, V = 7419.8(8) A(3), Z = 8. Moreover, 1a-c react with [Au(2)(dppm)Cl(2)] to form new heterobridged trithiophosphonate complexes of the type [Au(2)(dppm)(S(2)P(S)R)] (R = Fc (12)). The luminescence properties of several structurally characterized complexes have been investigated. Each of the title compounds luminesces at 77 K. The results indicate that the nature of Au...Au interactions in the solid state has a profound influence on the optical properties of these complexes.

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PubMed2002

19F, (1)H-HOESY and PGSE NMR studies of neutral trinuclear complexes of Au(I) and Hg(II): evidence for acid-base stacking in solution.

By combining the information from 19F, 1H-HOESY and PGSE NMR methodologies, unprecedented direct evidence has been obtained for the formation of supramolecular assemblies in solution between the trinuclear cyclic AuI basic compounds ([Au(mu-C2,N3-bzim)]3 (bzim = 1-benzylimidazolate), 1, and [Au(mu-C,N-C(OEt)=N-p-C6H4-CH3)]3, 2, on one hand, and the trinuclear cyclic HgII acid complex [Hg(mu-C,C-C6F4)]3, 3, on the other hand. HOESY experiments indicate that a stacking similar to that observed in the solid state occurs. PGSE studies demonstrate the presence of an equilibrium between the free trinuclear entities and adduct A in the case of 2/3 admixtures (see Sketch) while for 1/3 admixtures, adducts A and B are mainly present in solution.

Journal Article↗
PubMed2002

Bis(3,5-dimethylpyrazole-kappaN2)silver(I) nitrate.

The two independent bis(3,5-dimethylpyrazole)silver(I) cations in crystalline [Ag(C(5)H(7)N(2))(2)]NO(3) display N-Ag-N angles of 175.51 (14) and 174.44 (13) degrees, and an average Ag-N distance of 2.124 (5) A. The nitrate anion is situated between [Ag(C(5)H(7)N(2))(2)]+ units and interacts via hydrogen bonds with the NH groups. The two 3,5-dimethylpyrazole ligands are trans about the silver center. Only a small deviation from linearity is observed in the coordination around silver.

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