Showing papers by "Brian W. Skelton published in 2010"
TL;DR: In this article, the binuclear binuclear complex of p-tert-butyltetrathetrathiatealix[4]arene has been studied and a variety of structurally characterised species containing oxo-, hydroxo- and aqua-ligands presumably derived from water present in the preparative medium, along with the thiacalixarene in various stages of deprotonation.
Abstract: Extension of previous work on the lanthanide(III) ion complexes of p-tert-butyltetrathiacalix[4]arene has led to a variety of structurally characterised species containing oxo-, hydroxo- and aqua-ligands presumably derived from water present in the preparative medium, along with the thiacalixarene in various stages of deprotonation. The overall stoichiometry of some species is remarkably complicated due to the presence of simple anions and multiple solvents. Simplest is the binuclear complex [(μ-H2O){Ln(O-dmf)2}2(HL·dmf)2]·nS (dmf = dimethylformamide) [1Ln, Ln = Sm (nS = 2dmf), Eu (nS = 1.5dmf·2MeCN)], also the best-defined of all the arrays studied. The heaviest lanthanides give trinuclear Ln(OH)3·2Ln(LH)·xdmf·yH2O (2Ln, Ln = Yb, Lu), while both oxo and hydroxo species are isolable with Eu: trinuclear Eu3O(L)(LH)(LH4)·13dmf (3) and tetranuclear Eu4O(OH)2(L)(LH2)2(LH4)·12dmf (9), both somewhat atypical species containing uncoordinated thiacalixarene molecules within the lattice. Anion (NO3, ClO4) coordination, as in the tri- and tetranuclear species, 4–6Ln, 9, 10Ln, 11Ln, 12, seems especially favoured for the lighter lanthanides. In these arrays, the Ln3 and Ln4 aggregates are triangular or (quasi-)square-planar, except for Gd4O2(LH2)4·2H2O·2MeOH·2dmf·3.375CH2Cl2 (12), where there is a Z-disposition. Most common is an Ln3O core, which spans the gamut of Ln in three sets of crystal forms with cells of similar dimensions: for Ln = La...Nd, Ln3(OH)(NO3)4(LH2)2·4.5dmf (5Ln) (space group C2/m), and Sm...Lu, Ln3O(NO3)(LH)2·4H2O·2dmso·2MeCN·3py (6Ln) (space group P21/n), conformity with crystallographic symmetryentails disorder of the Ln atoms; in a further form of lowersymmetry Pn, (pyH)Ln3O(NO3)2(LH)2·2MeCN·xH2O·ydmso·1.5py·MeOH (7Ln, Ln = La, Ce), with no imposed crystallographic symmetry, some disorder persists, but none is found in the crystallographically unrelated form of 8Pr, Pr3O(NO3)(LH)2·16H2O·2MeCN·5py. Ln4(OH)(NO3)3(L)2·8dmf·2dmso·3H2O (10Ln, Ln = Pr...Gd, previously defined for Nd) has a square-planar Ln4O array sandwiched between a pair of L ligands, with a similar form found for Ln4O(ClO4)2(L2)·xdmf·yH2O (11Ln, Ln = La...Nd).
80 citations
TL;DR: In this article, X-ray crystal structures of three dicarboxylato-bis-α-hydroxyoximenickel(II) complexes have been obtained, which contain a short chained (C8) analogue of LIX®63 hydroxyoxime, along with either benzoate, isobutyrate or propionate.
Abstract: X-ray crystal structures of three dicarboxylato-bis-α-hydroxyoximenickel(II) complexes have been obtained. These contain a short chained (C8) analogue of LIX®63 hydroxyoxime, along with either benzoate, isobutyrate or propionate. All have pseudo-octahedral structures with monodentate carboxylate anions located cis to one another and neutral, chelating α-hydroxyoxime ligands. Intra-molecular hydrogen bonding between each anionic acid's carboxylate group and an adjacent oxime hydroxyl group is evident. Inter-molecular hydrogen bonding is also observed. These provide the first definitive structural elucidation of the types of nickel complexes that could be formed during synergistic extraction by LIX®63 and carboxylic acids.
34 citations
TL;DR: This study greatly extends the knowledge of the complex chemistry of silver(i) halides with tu by synthesizing, single crystal X-ray structural and spectroscopic characterizations and diagnosis bands in the IR and far-IR spectra of all of the synthesized complexes are assigned and interpreted.
Abstract: Syntheses, single crystal X-ray structural and spectroscopic characterizations are described for a variety of adducts of silver halides with thiourea (‘tu’), N-ethylthiourea (‘ettu’ = EtNH·CS·NH2) and N,N′-diethylthiourea (‘detu’ = EtNH·CS·EtNH). This study greatly extends our knowledge of the complex chemistry of silver(I) halides with tu. The unexpected diversity of composition of such complexes was initially revealed by the powerful mechanochemical/IR method and the structures of several of the new complexes were determined by X-ray crystallographic studies of samples subsequently prepared from aqueous solution. Structural characterizations provide extensive geometrical data for (mononuclear 1 : 3) [XAg(xtu)3] arrays (xtu = ettu, detu; X = Cl, Br, I), assisting vibrational spectroscopic assignments. With the parent tu ligand, binuclear ionic forms are obtained: [tu2Ag(μ-tu)2Agtu2]X2, the chloride as the dihydrate and the bromide as a di(thiourea) dihydrate adduct. With tu 1 : 2 complexes are defined for X = Cl, Br, as isomorphous one-dimensional polymers; AgCl:tu (1 : 1) is a two-dimensional net with six-membered Ag3S3 rings and terminal chloride. Intermediate stoichiometries are defined in AgBr:tu (2 : 3), a one-dimensional polymer of Ag2S2 rhombs linked at the silver atoms, while [Cl2Ag3(tu)4](NO3)·H2O is also a one-dimensional polymer in which chloride and thiourea sulfur atoms link six-membered Ag3S3 rings. Diagnostic bands in the IR and far-IR spectra of all of the synthesized complexes are assigned and interpreted in relation to the structures.
33 citations
TL;DR: A Ru(II) complex has been isolated that contains an ortho-xylylene-linked bis(NHC)cyclophane (NHC = N-heterocyclic carbene) that binds to the Ru centre through two carbene carbons and one of the arene rings in an eta(6)-mode.
Abstract: Using two different reaction procedures, a Ru(II) complex has been isolated that contains an ortho-xylylene-linked bis(NHC)cyclophane (NHC = N-heterocyclic carbene) that binds to the Ru centre through two carbene carbons and one of the arene rings in an η6-mode.
29 citations
TL;DR: These studies provide the first evidence in support of one of the indicated treatments with Aconitum orochryseum in Bhutanese traditional medicine and this alkaloid represents a potential new antimalarial structural lead.
27 citations
TL;DR: In this paper, the 2-organochalcogenomethylpyridine motif with substituents in the four or six position of the pyridyl ring, R4,R6-pyCH2ER1 [R4 = R6 = H, ER1 = SMe (1), SeMe (2), SPh (6), SePh (7), R4 = Me, R6=H, R1EER1, R2EER2, R3EER3, R5EER4, R
25 citations
TL;DR: In this article, the synthesis of osmium complexes in the presence of KF/NaBPh 4 is described and the molecular structure of x ǫ = 3 has been determined by a single crystal XRD study.
23 citations
TL;DR: In this article, structural characterisation of complex complexes formed between main group 1 metal ions and p-tert-butyltetrathetrathiatealixarene, LH4 is presented.
Abstract: In extension of previous work involving structural characterisation of complex salts formed between main group 1 metal ions and p-tert-butyltetrathiacalixarene, LH4, the present study encompasses complexes with a wider array of main group 2, 13, 14 metal ions. For group 2, single-crystal X-ray structural characterisation of Ca(LH3)2·3dmf (1a), {Ca(LH2)·3dmf}2 (1b), Ba(LH3)2·6dmf (2a) and BaCO3·3Ba(LH3)2·3H2O·3CH3CN·12.25CH2Cl2 (2b) provides models for various coordination units. For group 13, this applies to {Ga(OH)(LH2)·3.5dmf}2 (3), {In(LH)·4EtOH·2CH2Cl2}2 (4a) and {In(OH)(LH2)·3CH2Cl2}4 (4b), and for group 14, to OPb4(LH)2·6dmf·dmso·2H2O (5). Overall, these define mononuclear (1a, 2a), binuclear (1b, 3, 4b) and tetranuclear (2b, 4b, 5) species. The calixarene cavities frequently include solvent molecules, though this capacity is clearly influenced by the nature of the bound metal ion(s) and their binding, as well as the associated impact on the conformation of the calixarene ligand(s).
22 citations
TL;DR: Three pentanuclear lanthanoid hydroxo clusters of composition [Ln(OH)(5)(abzm)(10)], where Ln = Eu, Tb, Ho and abzm = di(4-allyloxy)benzoylmethanide, have been prepared and exhibit Curie-Weiss Law behaviour, displaying antiferromagnetic ordering at low temperatures.
Abstract: Three pentanuclear lanthanoid hydroxo clusters of composition [Ln(OH)5(abzm)10], where Ln = Eu, Tb, Ho and abzm = di(4-allyloxy)benzoylmethanide, have been prepared. The structures have been characterised by means of IR, Raman, elemental analyses and X-ray diffraction, showing a pyramidal square-based cluster core. The clusters (Tb and Ho) exhibit Curie–Weiss Law behaviour, displaying antiferromagnetic ordering at low temperatures. The emission properties of the Eu cluster demonstrate the abzm− ligand is an efficient antenna (λex = 420 nm) only for the sensitisation of Eu luminescence in the visible range, via energy transfer to the 5D0 state of the trivalent metal. The clusters have been reacted in the presence of methyl methacrylate and azobisisobutyronitrile to prepare reinforced polymers via radical polymerisation. The obtained materials exhibit swelling upon immersion into organic solvents up to ≈ 110% of their original size, in agreement with the presence of cluster-crosslinked polymeric chains. Also, no loss of transparency was observed in the preparation of the materials. The characteristic red emission of the Eu cluster in also retained in the polymeric material.
22 citations
TL;DR: In this paper, the X-ray determined structure of 3 showed a planar centrosymmetric Au4 rhomb, two opposed Au atoms being σ-bonded to the C C group, while the other two Au atoms are each η 2-bunded to C C groups and a PPh3 ligand.
21 citations
TL;DR: The molecular structures of eight complexes are reported, including a re-determination of 1, andputed NMR chemical shifts are used to reassign the butadienyl carbon resonances in the (13)C NMR spectrum of 1.
Abstract: In the η3-butadienyl complex Ru{η3-C(CN)2CPhCC(CN)2}(PPh3)Cp 1, which is formed from Ru(CCPh)(PPh3)2Cp and tcne, a CN group reacts with MeO− to give the methoxy-amide Ru{NHC(OMe)C(CN)CCPhC(CN)2}(PPh3)Cp 2, in which the NH has displaced the CC from the Ru centre with formation of a RuC3N ring. “Click addition” of azide to a CN group in 1 gives the oligomeric tetrazolato complex Ru{N3N[Na(OEt2)]CC(CN)CCPhC(CN)2}(PPh3)Cp 3, also containing a RuC3N ring. Salt-elimination reactions of 3 with MeOTf, FeCl(dppe)Cp, RuCl(dppe)Cp* and trans-PtCl2{P(tol)3}2 result in selective substitution at one nitrogen atom of the RuC3N ring. Geometries of 1 and the anion in 3 were computed by DFT methods. Preferences for CN groups attacked in the nucleophilic and cycloaddition reactions of 1 are supported by NBO calculations. Alkylation of 1 in reactions with 1,2-dimethoxyethane gave two isomers of Ru{N3[CH(CH2OMe)(OMe)]NCC(CN)CCPhC(CN)2}(PPh3)Cp 8 and 9, differing in the sites of attachment of the alkyl group, likely by radical processes. The molecular structures of eight complexes are reported, including a re-determination of 1. Computed NMR chemical shifts are used to reassign the butadienyl carbon resonances in the 13C NMR spectrum of 1.
TL;DR: In all, the calixarene hexa-anion is present in a virtually identical conformation, suggesting that conformational preferences of the ligand must be a major factor controlling the form of the bound oxo-metal complex.
Abstract: Formation of uranyl ion complexes of p-t-butylcalix[8]arene by reaction of the calixarene with [UO2(dmso)5]2+ in the presence of various bases leads to the crystallisation of solids with interestingly different stoichiometry, involving both di- and tri-uranate oligomers bound to the calixarene in anionic species. In all, the calixarene hexa-anion is present in a virtually identical conformation, suggesting that conformational preferences of the ligand must be a major factor controlling the form of the bound oxo-metal complex. Hydrogen bonding to the anions does not appear to be prominent even in the presence of protonated amines and this may explain the formation of some remarkable cation/solvent/simple anion clusters found within the lattices.
TL;DR: The formation and interesting reactivity of several azepino[4,5-b]indole heterocycles are reported, which results in an unprecedented secondary reaction of the Criegee intermediate to afford a benzo[c]naphthyridione containing a bridging cyclic peroxide.
Abstract: Herein we report the formation and interesting reactivity of several azepino[4,5-b]indole heterocycles. Initially, a key intramolecular Heck reaction is used to efficiently create the azepino[4,5-b]indole seven membered ring containing an exocyclic double bond. Treatment of the olefin with ozone results in an unprecedented secondary reaction of the Criegee intermediate, through intramolecular olefin trapping, to afford a benzo[c]naphthyridione containing a bridging cyclic peroxide.
TL;DR: New insights are gained into the extraction of structural information concerning the hapticity (κ(2) or κ(3)) of the poly(pyrazolyl)borate ligands to the Rh metal by using quantum-chemical methods to assist reliable assignments of the experimental values.
Abstract: Novel [Rh(η-diene)Tpx] complexes of sterically encumbered Tpx ligands (Tpx = Tp4Bo, diene = cod, 1; nbd, 2; Tpx = Tp4Bo,5Me, diene = cod, 3; nbd, 4; Tpx = Tpa,3Me, diene = cod, 5; nbd, 6; Tpx = Tpa*,3Me, diene = cod, 7; nbd, 8) have been prepared by treatment of [Rh(η-diene)(μ-Cl)]2 with TlTpx (Tpx in general, in detail: Tp4Bo = hydrotris(indazol-1-yl)borate, Tp4Bo,5Me = hydrotris(5-methyl-indazol-1-yl)borate, Tpa,3Me = hydrotris(3-methyl-2H-benz[g]-4,5-dihydroindazol-2-y1)borate, Tpa*,3Me = hydrotris(3-methyl-2H-benz[g]indazol-2-yl)borate), and characterized by analytical and spectral data (IR, 1H, 11B, and 13C NMR solution). The structures adopted by [Rh(nbd)Tp4Bo] 2, [Rh(cod)Tp4Bo,5Me] 3, [Rh(nbd)Tpa,3Me] 6, [Rh(nbd)Tpa*,3Me] 8, and [Rh(nbd)Tpa*,3Me*] 8* (incorporating a borotropomeric ligand), have been investigated. Low steric hindrance between the ligands in 2 and 3 permits κ3 coordination of the pyrazolylborate while the high steric encumbrance present in 6, 8, and 8* results in κ2 ligands. The coo...
TL;DR: The generation of amphiphiles derived from macrobicyclic hexamines of the "sarcophagine" class can be prepared through efficient and selective reactions involving the reductive alkylation, using long-chain aldehydes, of amino-functionalised sarcophagines when bound to Cu(ii) or Mg(ii).
Abstract: The generation of amphiphiles derived from macrobicyclic hexamines of the “sarcophagine” class can be prepared through efficient and selective reactions involving the reductive alkylation, using long-chain aldehydes, of amino-functionalised sarcophagines when bound to Cu(II) or Mg(II). The Mg(II) pathway is particularly convenient for the ultimate isolation of the free ligands, which can then be used to form metalloamphiphiles with a variety of metal ions. Structural studies have been made of one of the free (protonated) ligands and some of their complexes.
TL;DR: In this paper, a stereo-specific reaction between triphenyl phosphite and dialkyl acetylenedicarboxylates in the presence of a series of halogenated anilines is described.
Abstract: New phosphonate ester derivatives were obtained by in situ stereo-specific reaction between triphenyl phosphite and dialkyl acetylenedicarboxylates in the presence of a series of halogenated anilines. Spectroscopic data and X-ray crystallography analysis are in agreement with the gauche arrangement for the two vicinal protons in the structures. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:222–227, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20600
TL;DR: In this paper, the cationic mixed-metal cluster diynyl complexes were determined by single-crystal XRD studies, and it was shown that extensive disproportionation occurs in solution.
TL;DR: A facile one-pot procedure, or so-called direct synthesis, was used to prepare the novel heterometallic complexes [M{sub 2}Mn(OAc){sub 6}(bpy){sub 2]], where M=Cu (1), Co, Zn, bpy=2,2'-bipyridyl, with high yields via oxidative dissolution of pure metals in a liquid phase.
TL;DR: In this article, three unusual sesquiterpenes (1, 3 ) were isolated from the tropical rainforest basidiomycete, Marasmiellus troyanus and their structure elucidation was achieved by NMR spectroscopy, single-crystal X-ray structural analysis and a modified Mosher's ester method to determine the absolute stereochemistry of compound 1.
TL;DR: CoCl2 was treated with 1, 2, and 6 eq. of 2,6-bis(5-phenylpyrazol-3-yl)pyridine (H2L) yielding respectively the monosubstituted [Co(H 2L)Cl2], the disubstitized [Co[Co[H]2]2][PF6]2, and a supramolecular assembly formed by a central disubstrituted octahedral complex and four more hydrogen bonded peripheral ligands, as illustrated by X-ray crystal
Abstract: CoCl2 was treated with 1, 2, and 6 eq. of 2,6-bis(5-phenylpyrazol-3-yl)pyridine (H2L) yielding respectively the monosubstituted [Co(H2L)Cl2], the disubstituted [Co(H2L)2][PF6]2, and a supramolecular assembly formed by a central disubstituted octahedral complex and four more hydrogen bonded peripheral ligands, [{Co(H2L)2}(H2L)4][PF6]2, as illustrated by X-ray crystal structure analysis.
TL;DR: In this article, structural characterisation of a number of hydrated solids containing chiral, kinetically inert [Co(A-A)3]3+ cations (A,A = 2,2′-bipyridine, 1,10-phenanthroline, 4,4′-dimethyl-2,2.2′)-dimethyl and chiral kinetically labile [Ln(dipic)3]-anions (Ln,Dipic)-anions are presented.
Abstract: Structural characterisation of a number of hydrated solids containing chiral, kinetically inert [Co(A–A)3]3+ cations (A–A = 2,2′-bipyridine, 1,10-phenanthroline, 4,4′-dimethyl-2,2′-bipyridine) and chiral, kinetically labile [Ln(dipic)3]3– anions (Ln = La, Eu, Tb, Ho, Er, Lu, Y, though not for all cobalt cations; dipic = dipicolinate = pyridine-2,6-dicarboxylate) show a remarkable range of associations between the lattice components, though all are racemic arrays Analysis of the structures in terms of short interatomic contacts between the components shows that, whereas numerous contacts of the heteroaromatic ligands do occur, very few define an arrangement which could be truly termed “π-stacking” where the rings are closely parallel and atom overlaps in projection are substantial Water is important in the highly hydrated lattice structures, not only because of hydrogen-bonding interactions with itself and carboxylate-O atoms but also because of its interactions with the aromatic units The family [Co(bipy)3][Ln(dipic)3]·~13H2O are essentially isomorphous for the full range of Ln plus Y (triclinic, P\bar{1}, a = 123, b = 143, c = 165 A, α = 94, β = 94, γ = 108 ˚, Z = 2) Among the heavier lanthanides, the potential symmetry of the anion/cation combination is realised in the trigonal space group P\bar{3}, both species lying together as an ion-pair, disposed on the trigonal axis for [Co(phen)3][Ln(dipic)3]·22H2O (Ln = Eu, Er; a = 152, c = 168 A, Z = 2)
TL;DR: The redox properties and electronic structure of the C4-bridged bis-cluster 6 have been investigated through a combination of cyclic voltammetry, IR spectroelectrochemistry and DFT calculations, with comparisons made with suitable model systems.
Abstract: Reactions of CCo3 carbonyl clusters Co3(μ3-CR)(CO)9 with 2,4,6-trimethyl-1,3,5-trithiane (SMe3) have given Co3(μ3-CR)(μ3-SMe3)(CO)6 [R = H (1), CCSiMe3 (2)] A small amount of the coupled-alkyne product Me3SiC2[Co2(CO)6]C2[Co2(μ-SMe3)(CO)4]CCSiMe3 (3) was isolated from the latter reaction The reaction of Co3(μ3-CCCSiMe3)(μ3-SMe3)(CO)6 (2) with AuCl(PPh3) in the presence of NaOMe gave Co3{μ3-CCCAu(PPh3)}(μ3-SMe3)(CO)6 (4), which in turn reacts with Co3(μ3-CBr)(CO)9 in the presence of catalytic amounts of Pd(PPh3)4 and CuI to give {(OC)9Co3}(μ-CCCC){Co3(μ3-SMe3)(CO)6} (5) Further substitution of 5 with SMe3 gave symmetrical {Co3(μ3-SMe3)(CO)6}2(μ-CCCC) (6), also obtained from a reaction between {Co3(CO)9}2(μ-CCCC) and two equivalents of SMe3 Similar substitution of Co3{μ3-C(CC)2[Ru(dppe)Cp*]}(CO)9 with SMe3 gave Co3{μ3-C(CC)2[Ru(dppe)Cp*]}(μ3-SMe3)(CO)6 (7) In all of these compounds, the SMe3 ligand caps the basal face of the CCo3 cluster on the opposite side to the μ3-CR group The three S donors occupy axial sites, with all CO groups being in equatorial sites Reactions of Co3(μ3-CBr)(CO)9 with SMe3 gave only Co3(μ3-CX)(μ3-SMe3)(CO)6 [X = C(O)NMe2 (8), CO2H (9)] The redox properties and electronic structure of the C4-bridged bis-cluster 6 have been investigated through a combination of cyclic voltammetry, IR spectroelectrochemistry and DFT calculations, with comparisons made with suitable model systems Single-crystal X-ray diffraction structure determinations of 1, 2, 3, 4 and 8 are reported
TL;DR: In this paper, the cyanated fluorocarbon ligand is shown to be a very powerful electron-withdrawing group and can be converted to Ru{C C(c-C5F4Cl[ C(CN)2])}(dppe)Cp∗ 6 by treatment with CH2(CN)/basic alumina.
TL;DR: Single-crystal XRD structure determinations of several products are reported together with that of precursor {Co(3)(mu-dppm)(CO)(7)}.
Abstract: Treatment of Co3(μ3-CCCR)(μ-dppm)(CO)7 with O2 (air) in the presence of [FcH]PF6 afforded Co3{μ3-CC(O)R}(μ-dppm)(CO)7 by the formal conversion –CC– + O–O → >C–O + CO. In this way, complexes with R = Ph, Fc, and W(CO)3Cp, bis-clusters {Co3(μ-dppm)(CO)7}2{μ3:μ3-[C(O)(CC)C]}, {Co3(μ-dppm)(CO)7}2{μ3:μ3-[C(O)(CC)xC(O)C]} (x = 1, 2), and {Co3(μ-dppm)(CO)7}2{μ3:μ3-[CC(O)CCC6H4CCC(O)C]}, and heterometallic bis-clusters {Co3(μ-dppm)(CO)7}{μ3:μ3-[CC(O)CCC]}{M3(μ-H)3(CO)9} (M = Ru, Os) have been prepared. Single-crystal XRD structure determinations of several products are reported together with that of precursor {Co3(μ-dppm)(CO)7}2{μ3:μ3-[C(CC)2C6H4(CC)2C]}.
TL;DR: In this article, a doubly deprotonated trans-N,N′-dimethyl-meso-octaethylporphyrinogen (MEMP) was synthesized as tetrahydrofuran adducts (Sm and Eu, bis; Yb, mono) by metathetical exchange reactions of the dipotassium macrocyclic precursor complexes with the corresponding metal diiodides in tetrahedron.
TL;DR: Hirshfeld surface analysis has revealed that molecules in crystalline MTEP are weakly polar, and aggregate through nonclassical C--H...N hydrogen bonds, which makes it unlikely that MTEP is protonated in its biologically active form.
TL;DR: X-ray structure determinations indicate that there is negligible perturbation of the physical dimensions of the thiophene moieties by the cage substituent and thus that the resistance to polymerization must be associated with the high positive charge carried by these substituents.
Abstract: Various 2- and 3-thienylmethylamino-substituted cobalt(III) cage amine complexes, prepared with the objective of obtaining cage-functionalized polythienyls, have been found to be resistant to oxidative polymerization by both electrochemical and chemical procedures. X-ray structure determinations indicate that there is negligible perturbation of the physical dimensions of the thiophene moieties by the cage substituents and thus that the resistance to polymerization must be associated with the high positive charge carried by these substituents.
TL;DR: The 1:1 tribenzylphosphane (PBn3) complexes of gold(I)-[(Bn3P)AuX] (X = Cl and Br) have been synthesized, and their structures were determined by single-crystal X-ray crystallography.
Abstract: The 1:1 tribenzylphosphane (PBn3) complexes of gold(I)-[(Bn3P)AuX] (X = Cl and Br) have been synthesised, and their structures were determined by single-crystal X-ray crystallography. The compounds are isomorphous, neutral molecules with linearly coordinated P-Au-X arrays. Each structure contains three independent [(Bn3P)AuX] entities lying on the three threefold axes of space group P3c1. The mean bond lengths are Au-Cl 2.302(8), Au-P 2.227(11) angstrom for the chloride and Au-Br 2.404(10), Au-P 2.229(4) angstrom for the bromide. These contrast with the 1:1 adducts previously reported for copper(I), which take the form [Cu(PBn3)(2)][CuX2]. The 1:2 AuX:PBn3 compounds that have been synthesised are formulated as [Au(PBn3)(2)]X center dot nH(2)O (X = Cl, n = 1 or 2; X = I and BF4, n = 0). Single-crystal X-ray structures show that linearly two-coordinate centrosymmetric [Au(PBn3)(2)](+) arrays are found in [Au(PBn3)(2)]Cl center dot H2O and (Au(PBn3)(2)]BF4 with Au-P bond lengths of 2.2988(7) and 2.3016(7) angstrom for the chloride and 2.2975(7) angstrom for the tetrafluoroborate. v(AuX) bands in the far-IR spectra of [(Bn3P)AuX] are assigned at 320 and 227 cm(-1) for X = Cl and X = Br, respectively. The P-31 CP MAS NMR spectra of [(Bn3P)AuX] (X = Cl, Br) and [Au(PBn3)(2)]X (X = Cl center dot H2O, Cl center dot 2H(2)O, I, BF4) are reported, and the observation of (2)J(PP) coupling in the spectrum of [Au(PBn3)(2)]Cl center dot 2H(2)O is consistent with the presence in this complex of noncentrosymmetric cations in which the two phosphorus atoms are inequivalent.
TL;DR: In this paper, a multiple-component bilayer involving four different ions has preferential binding of functionalized 3-(2-hydroxyethyl)-1-methylimidazolium in the cavity of bowl-shaped p-sulfonatocalix[4]arene.
Abstract: A multiple-component bilayer involving four different ions has preferential binding of functionalized 3-(2-hydroxyethyl)-1-methylimidazolium in the cavity of bowl-shaped p-sulfonatocalix[4]arene, with the supermolecule being capped by a water molecule involving an O–H···π(imidazolium) interaction, an O···HO H-bond involving the hydroxyethyl group, and an SO···HO H-bond. The nature of the interplay of the components has been mapped out using Hirshfeld surface analysis. The [imidazolium ∩ calixarene] supermolecule persists in solution.
TL;DR: In this paper, a 1D aqua-bridged polymer with an ambidentate Ni(OAc) 4 2- fragment has been characterized, which has not been previously characterized.
Abstract: A one-pot reaction of copper powder and nickel and ammonium acetates in a CH 3 OH solution of ethylenediamine (en) yields a unique 1D aqua-bridged polymer [Cu(en) 2 (μ 2 -H 2 O) 2 -Ni(OAc) 4 ] n ·4nH 2 O (1) with an ambidentate Ni(OAc) 4 2- fragment that has not been previously characterized. The basic structural motif of 1 contains a previously unreported hetero-metallic M(μ 2 -H 2 O)M' aqua-bridge chain with alternating metal atoms. A complex system of N/O-H···O hydrogen bonds strengthens the polymeric chains and links them into a supramolecular three-dimensional network. Variable-temperature magnetic susceptibility measurements of 1 revealed a weak ferromagnetic coupling (J = 1.1 cm -1 ) between the paramagnetic copper(II) and nickel(II) ions, which is transmitted through the oxygen bridges.