$^{1}_{\infty}\rm [M^{II}(Py)_{2}(H_{2}O)_{n}(ADC)_{2/2}]$ mit MII = Fe,Co, Ni (n = 2) und MII = Cu (n = 1): Vier neue Koordinationspolymere mit dem Acetylendicarboxylat‐Dianion (ADC2−) als verbrückendem Liganden

with M^II = Fe, Co, Ni (n = 2) and M^II = Cu (n = 1): Four New Coordination Polymers with Acetylenedicarboxylate (ADC^2?) as Bridging Ligand By slow diffusion of pyridine (Py) into an aqueous solution of a respective metal salt and acetylenedicarboxylic acid (H₂ADC) single crystals of new coordination polymers of composition (M = Fe, Co, Ni; C2/c, Z = 4) ( 1 – 3 ) and (P2₁2₁2₁, Z = 4) ( 4 ) were obtained. In compounds 1 – 3 octahedral M^IIO₄N₂ units are connected via acetylenedicarboxylate anions to form chain‐like polymers. In compound 4 square pyramidal Cu^IIO₃N₂ units are found, which are also connected to chains by acetylenedicarboxylates. Thermoanalytical investigations on 3 show an abrupt mass loss of approx. 40 % above 130 °C, which points to a release of both pyridine ligands (calc.: 43 %). Thereafter, the sample decomposes continuously, which is confirmed by XRPD measurements, as an amorphous residue is found. Magnetic susceptibility measurements of 1 – 3 display paramagnetic behaviour in the temperature range 2‐300 K. While μ_eff of 3 (d⁸ configuration) with orbital singlet ground state is nearly temperature‐independent, 1 (d⁶) and 2 (d⁷) exhibit complicated μ_eff?T behaviour on account of a ligand‐field ground state derived from the cubic states ⁵T₂ and ⁴T₁, respectively. On the basis of a tetragonal ligand‐field model excellent adaptations are obtained with reasonable ligand‐field parameters. Exchange interactions between the magnetic ions are detected in no case.     

Chiral Coordination Polymers with Amino Acids: $\rm ^{2}_{\infty}[Cu_{2}(\mu-L-tryptophanato)_{2}(\mu-4,4\prime-bipyridine)(H_{2}O)_{2}](NO_{3})_{2}$

The two‐dimensional mixed‐ligand network catena‐[(μ‐4,4′‐bipyridine)‐bis(μ‐L‐tryptophanato‐κ³N,O,O′)‐diaqua‐dicopper(II) dinitrate] is constructed through the bridging action of both the tridentate amino carboxylato and the bidentate 4,4′‐bipyridine ligand. The enantiomeric L‐tryptophanato ligand acts as an N,O chelate towards one copper atom and bridges through the second carboxylate oxygen atom to the adjacent copper ion. Stacking of the corrugated nets creates channels which are occupied by the hydrogen‐bonded and very weakly Cu‐coordinating nitrate ions.     

Synthesis and Crystal Structure of Hexakis(N—allylthiourea)tetracopper(I) Tetratrifluoromethanesulfonate, [Cu4{CH2=CHCH2NHC(S)NH2}6](SO3CF3)4

Hexakis(N—allylthiourea)tetracopper(I) Tetratrifluoromethanesulfonate, [Cu₄{CH₂=CHCH₂NHC(S)NH₂}₆](CF₃SO₃)₄ (sp.gr.P2₁/n, a = 13.5463(8), b = 24.129(2), c = 19.128(1)Å, β = 108.053(6)°, Z = 4, R = 0.0440 for 13548 unique reflections) was obtained by reduction of Cu(CF₃SO₃)₂ with excess of N—allylthiocarbamide in benzene medium. Four crystallographical independent Cu atoms possess trigonal environment of three S atoms of CH₂=CHCH₂NHC(S)NH₂ moiety and form Cu₄S₆⁴⁺ adamantane—like fragments. The latteres are connected with CF₃SO₃^— anions via (C)—H···F hydrogen bonds.     

Chemical Conversion of Hg‐Clusters: Synthesis and Crystal Structure of $ {\rm [(DMSO)_2 Co(NC \overline{S)_4(Hg}-TePh)_2]_{\rm n} }$, the First Compound Containing a Polymeric Hg—Te Chain

The six‐membered ring Hg₃Te₃ of [Hg₃Cl₃(μ‐TePh)₃]·2 DMSO {(Ph = C₆H₅; DMSO = (CH₃)₂SO} was opened by redissolution with DMSO, reacting with Co[Hg(SCN)₄] and affording polymeric . The monoclinic novel compound belong to the space group P2₁/n and assembles in a bidimensional lattice tetrahedral Hg^II(SCN)₂Te₂‐ and octahedral Co^II(NCS)₄(DMSO)₂‐chains linked trough SCN bridges along the crystallographic axis b and diagonally to the ac axes. The structure of [(DMSO)₂Co(NCS)₄(Hg—TePh)₂]_n is limited by the DMSO ligands in the axial positions of the Co‐octahedrons.     

Syntheses and Crystal Structures of Ammoniates with the Phenyl‐Substituted Polytin Anions Sn2Ph$\rm{_{\bf 4}^{{\bf 2} - } }$, cyclo‐Sn4Ph$\rm{_{\bf 4}^{{\bf 4} - } }$, and Sn6Ph$\rm{_{{\bf 12}}^{{\bf 2} - } }$

The reaction of diphenyltin dichloride with the binary Zintl phase K₄Sn₉ in the presence of excess lithium and 18‐crown‐6 in liquid ammonia led to the ammoniate [K(18‐crown‐6)(NH₃)₂]₂Sn₂Ph₄ ( 1 ). The analogous reaction with K₄Ge₉ and potassium in the absence of further alkali metal ligands resulted in the compound [K₂(NH₃)₁₂]Sn₆Ph₁₂ ? 4 NH₃ ( 3 ). Cs₆[Sn₄Ph₄](NH₂)₂ ? 8 NH₃ ( 2 ) was prepared by reacting diphenyltin dichloride with a surplus of caesium in liquid ammonia. The low‐temperature single‐crystal structure determinations show all compounds to contain phenyl‐substituted polyanions of tin. Compound 1 is built from Sn₂Ph anions consisting of Sn dumbbells with two Ph substituents at each Sn‐atom. Compound 2 contains cyclo‐Sn₄Ph anions formed by a four‐membered tin ring in butterfly conformation with one Ph substituent at each Sn‐atom in an (all‐trans)‐configuration. Sn₆Ph in 3 is a zig‐zag Sn₆ chain with two substituents at each of the Sn‐atoms. Both 1 and 3 have molecular counter cations, in the latter case the unprecedented dinuclear potassiumammine complex [K₂(NH₃)₁₂]²⁺ is observed. Compound 2 shows a complicated three‐dimensional network of Cs? Sn interactions.     

Adipato‐Bridged Mixed Ligand catena Complexes: ${_{\infty}^1}${[M(phen)(H2O)]L2/2} with M = NiII,CuII, ZnII; H2L = Adipic Acid

Three adipato bridged mixed ligand catena complexes {[M(phen)(H₂O)]‐(C₆H₈O₄)_2/2} with M = Ni^II ( 1 ), Cu^II ( 2 ), Zn^II ( 3 ) were synthesized. Structure determination based on X‐ray diffraction shows that they crystallize isostructurally in the monoclinic space group C2/c (no. 15) with cell dimensions of: 1 a = 22.451(4)Å, b = 9.041(1)Å, c = 17.440(2)Å, β = 103.41(1)°, U = 3443.4(9)ų, Z = 8; 2 a = 22.479(2)Å, b = 9.067(1)Å, c = 17.494(3)Å, β = 103.67(1)°, U = 3464.6(8)ų, Z = 8; 3 a = 22.635(3)Å, b = 9.052(1)Å, c = 17.571(3)Å, β = 103.24(1)°, U = 3504.5(9)ų, Z = 8. The crystal structure consists of 1D {[M(phen)(H₂O)]‐(C₆H₈O₄)_2/2} zigzag chains, in which the metal atoms are all octahedrally coordinated by two N atoms of one phen ligands and four O atoms of one H₂O molecule and two adipato ligands. The zigzag chains are held together by interchain π‐π stacking interactions and interchain hydrogen bonds.     

Two Glutarato Bridged Coordination Polymers: ${_{\infty}^1}${[Mn(phen)]2L4/2} and ${_{\infty}^1}${[Zn(phen)(H2O)]L2/2}·H2O with H2L = Glutaric Acid

Two new glutarato bridged coordination polymers {[Mn(phen)]₂(C₅H₆O₄)_4/2} ( 1 ) and {[Zn(phen)(H₂O)](C₅H₆O₄)_2/2}· H₂O ( 2 ) were structurally characterized on the basis of single crystal X‐ray diffraction data. Crystal data: ( 1 ) P2/c (no. 13), a = 10.340(2)Å, b = 10.525(2)Å, c = 13.891(2)Å, β = 98.31(1)°, U = 1495.9(5)ų, Z = 2; ( 2 ) P2₁/n (no. 14), a = 6.738(1)Å, b = 25.636(3)Å, c = 10.374(1)Å, β = 106.13(1)°, U = 1721.4(4)ų, Z = 4. Complex 1 consists of 1D ribbon‐like {[Mn(phen)]₂(C₅H₆O₄)_4/2} chains, in which the [Mn(phen)] units were interlinked by glutarato ligands to generate 8‐ and 16‐membered rings. The Mn atoms are octahedrally coordinated by two N atoms of one phen ligand and four O atoms of three glutarato ligands with d(Mn‐N) = 2.270, 2.276Å, d(Mn‐O) = 2.114—2.283Å. Through the interchain π‐π stacking interactions, the 1D chains are assembled into 2D puckered layers, which are further held together by interlayer π‐π stacking interactions into a 3D network. Complex 2 is built up by 1D {[Zn(phen)(H₂O)](C₅H₆O₄)_2/2} linear chains and hydrogen bonded H₂O molecules. The Zn atoms are coordinated by two N atoms of one phen ligand and three O atoms of one H₂O molecule and two glutarato ligands to form slightly elongated trigonal bipyramids with the water O atom and one phen N atom at the apical positions (d(Zn‐N) = 2.101, 2.168Å, d(Zn‐O) = 1.991—2.170Å). The 1D linear chains result from [Zn(phen)(H₂O)] units bridged by bis‐monodentate glutarato ligands. The resulting 1D chains are assembled by π‐π stacking interactions into 2D layers, between which the hydrogen bonded H₂O molecules are situated.     

Luminescent Di‐ and Polynuclear Organometallic Gold(I)–Metal (Au2, {Au2Ag}n and {Au2Cu}n) Compounds Containing Bidentate Phosphanes as Active Antimicrobial Agents

The reaction of new dinuclear gold(I) organometallic complexes containing mesityl ligands and bridging bidentate phosphanes [Au₂(mes)₂(μ‐LL)] (LL=dppe: 1,2‐bis(diphenylphosphano)ethane 1 a , and water‐soluble dppy: 1,2‐bis(di‐3‐pyridylphosphano)ethane 1 b ) with Ag⁺ and Cu⁺ lead to the formation of a family of heterometallic clusters with mesityl bridging ligands of the general formula [Au₂M(μ‐mes)₂(μ‐LL)][A] (M=Ag, A=ClO₄^?, LL=dppe 2 a , dppy 2 b ; M=Ag, A=SO₃CF₃^?, LL=dppe 3 a , dppy 3 b ; M=Cu, A=PF₆^?, LL=dppe 4 a , dppy 4 b ). The new compounds were characterized by different spectroscopic techniques and mass spectrometry The crystal structures of [Au₂(mes)₂(μ‐dppy)] ( 1 b ) and [Au₂Ag(μ‐mes)₂(μ‐dppe)][SO₃CF₃] ( 3 a ) were determined by a single‐crystal X‐ray diffraction study. 3 a in solid state is not a cyclic trinuclear Au₂Ag derivative but it gives an open polymeric structure instead, with the {Au₂(μ‐dppe)} fragments “linked” by {Ag(μ‐mes)₂} units. The very short distances of 2.7559(6) Å (Au? Ag) and 2.9229(8) Å (Au? Au) are indicative of gold–silver (metallophilic) and aurophilic interactions. A systematic study of their luminescence properties revealed that all compounds are brightly luminescent in solid state, at room temperature (RT) and at 77 K, or in frozen DMSO solutions with lifetimes in the microsecond range and probably due to the self‐aggregation of [Au₂M(μ‐mes)₂(μ‐LL)]⁺ units (M=Ag or Cu; LL=dppe or dppy) into an extended chain structure, through Au? Au and/or Au? M metallophilic interactions, as that observed for 3 a . In solid state the heterometallic Au₂M complexes with dppe ( 2 a – 4 a ) show a shift of emission maxima (from ca. 430 to the range of 520‐540 nm) as compared to the parent dinuclear organometallic product 1 a while the complexes with dppy ( 2 b–4 b ) display a more moderate shift (505 for 1 b to a max of 563 nm for 4 b ). More importantly, compound [Au₂Ag(μ‐mes)₂(μ‐dppy)]ClO₄ ( 2 b ) resulted luminescent in diluted DMSO solution at room temperature. Previously reported compound [Au₂Cl₂(μ‐LL)] (LL dppy 5 b ) was also studied for comparative purposes. The antimicrobial activity of 1–5 and Ag[A] (A=ClO₄^?, SO₃CF₃^?) against Gram‐positive and Gram‐negative bacteria and yeast was evaluated. Most tested compounds displayed moderate to high antibacterial activity while heteronuclear Au₂M derivatives with dppe ( 2 a – 4 a ) were the more active (minimum inhibitory concentration 10 to 1 μg mL^?1). Compounds containing silver were ten times more active to Gram‐negative bacteria than the parent dinuclear compound 1 a or silver salts. Au₂Ag compounds with dppy ( 2 b , 3 b ) were also potent against fungi.     

Synthese und Struktur chiraler Heterometallatetrahedrane des Typs [Re2(M1PPh3)(M2PPh3)(μ‐PCy2)(CO)7C≡CPh] (M1 = Ag,Au; M2 = Cu,Ag, Au)

Syntheses and Structure of Chiral Metallatetrahedron Complexes of the Type [Re₂(M¹PPh₃)(M²PPh₃)(μ‐PCy₂)(CO)₇C≡CPh] (M¹ = Ag, Au; M² = Cu, Ag, Au) From the reaction of Li[Re₂(μ‐H)(μ‐PCy₂)(CO)₇(C(Ph)O)] ( 1 ) with Ph₃AuC≡CPh both benzaldehyde and the trinuclear complex Li[Re₂(AuPPh₃)(μ‐PCy₂)(CO)₇C≡CPh] ( 2a ) were obtained in high yield. The complex anion was isolated as its PPh₄‐salt 2b . The latter reacts with coinage metal complexes PPh₃M²Cl [M² = Cu, Ag, Au] to give chiral heterometallatetrahedranes of the general formula [Re₂(AuPPh₃)(M²PPh₃)(μ‐PCy₂)(CO)₇C≡CPh] (M² = Cu 3a , Ag 3b , Au 3c ). The corresponding complex [Re₂(AgPPh₃)₂(μ‐PCy₂)(CO)₇C≡CPh] ( 3d ) is obtained from the reaction of [Re₂(AgPPh₃)₂(μ‐PCy₂)(CO)₇Cl] ( 4 ) with LiC≡CPh. 3d undergoes a metathesis reaction in the presence of PPh₃CuCl giving [Re₂(AgPPh₃)(CuPPh₃)(μ‐PCy₂)(CO)₇C≡CPh] ( 3e ) and PPh₃AgCl. Analogous metathesis reactions are observed when 3c is reacted with PPh₃AgCl or PPh₃CuCl giving 3a or 3b , respectively. The reaction of 1 with PPh₃AuCl gives benzaldehyde and Li[Re₂(AuPPh₃)(μ‐PCy₂)(CO)₇Cl] ( 5a ) which upon reaction with PhLi forms the trinuclear complex Li[Re₂(AuPPh₃)(μ‐PCy₂)(CO)₇Ph] ( 6a ). Again this complex was isolated as its PPh₄‐salt 6b . In contrast to 2b , 6b reacts with one equivalent of Ph₃PAuCl by transmetalation to give Ph₃PAuPh and PPh₄[Re₂(AuPPh₃)(μ‐PCy₂)(CO)₇Cl] ( 5b ). The X‐ray structures of the compounds 3a , 3b , 3e and 4 are reported.     

Applications of NMR spectroscopy of chiral association complexes 5. Stereodynamics and diastereotopism in chiral 1,3-dienes \documentclass{article}\pagestyle{empty}\begin{document}${\rm HOCMe}_{\rm 2} \rlap{--} ({\rm CCl =\!= CCl\rlap{--})}_{\rm 2} {\rm X}$\end{document}

The barriers to partial rotation around the central single bond in chiral dienes \documentclass{article}\pagestyle{empty}\begin{document}${\rm HOCMe}_{\rm 2} \rlap{--} ({\rm CCl =\!= CCl\rlap{--})}_{\rm 2} {\rm X}$\end{document} have been determined by coalescence of either ¹H NMR signals (X = CH₂OCH₃) or ¹³C NMR signals (X = H). In the presence of the optically active shift reagent (+) ? Eu(hfbc)₃ all ¹H signals were split at temperatures where the interconversion of enantiomers is slow. The temperature dependence of these spectra also yielded free activation enthalpies for the enantiomerizations which were in agreement with the ones obtained without Eu(hfbc)₃. The assignment of the four methyl resonances appearing in the presence of (+) ? Eu(hfbc)₃ at low temperature was possible by gradually increasing the rate of enantiomerization or gradually replacing the optically active auxiliary compound by the racemic one.     

A Polymeric Arched Chain and a Chair‐like M2L2‐Metallamacrocycle Crystal Engineered of [M(phen)]2+ (M = Cu,Cd; phen = 1,10‐Phenanthroline) Corner Units and the Bent Ligand 4,4′‐Dithiodipyridine

Self‐assembly of Cd(phen)²⁺ and Cu(phen)²⁺ (phen = 1,10‐phenanthroline) building blocks with the bent ligand 4,4′‐dithiodipyridine (dtdp) has been investigated. Both building blocks serve as corner units with constrained cis‐geometry. The arched chain coordination polymer [{Cd(phen)(μ‐dtdp)(dtdp)(H₂O)}(ClO₄)₂·2CH₃OH·1.5H₂O]_n ( 1 ) crystallised from a mixture of Cd(ClO₄)₂·H₂O, phen and dtdp in methanol. The reaction of [Cu(phen)(H₂O)₂](CF₃SO₃)₂ ( 2 ) with dtdp in an ethanol/water mixture yielded a chair‐like metallamacrocycle, [{Cu(phen)(CF₃SO₃)₂}₂(μ‐dtpd)₂] ( 3 ). The crystal structure of the precursor complex 2 is also reported.     

Tetranuclear Complexes with {M4O4} (M = CoII,NiII) Cubane‐Like Core: Synthesis,Crystal Structure,and Magnetic Properties

Two tetranuclear clusters of formula [M₄L₄(HOMe)₄] {H₂L = (E)‐1‐[(2‐(hydroxymethyl)phenylimino)methyl]naphthalen‐2‐ol} [M = Co ( 1 ), Ni ( 2 )] were hydrothermally synthesized by reaction of M(OAc)₂ · 4H₂O with H₂L and NaOH in MeOH. X‐ray crystal structure analysis revealed that complexes 1 and 2 are isostructural. In the core of the structures, four M^II ions and four oxygen atoms occupied alternate vertices of [M₄O₄] cubane. The magnetic property measurements of 1 and 2 revealed that overall ferromagnetic M^II ··· M^II exchange interactions exist in both complexes.     

Hybrid Inorganic‐Organic Frameworks: Synthesis and Crystal Structures of RbFe(SO4)(C2O4)0.5·H2O and CsM(SO4)(C2O4)0.5·H2O (M = Mn,Fe)

Three new alkali metal transition metal sulfate‐oxalates, RbFe(SO₄)(C₂O₄)_0.5 · H₂O and CsM(SO₄)(C₂O₄)_0.5 · H₂O (M = Mn, Fe) were prepared through hydrothermal reactions and characterized by single‐crystal X‐ray diffraction, solid state UV/Vis/NIR diffuse reflectance spectroscopy, infrared spectra, thermogravimetric analysis, and powder X‐ray diffraction. The title compounds all crystallize in the monoclinic space group P2₁/c (no. 14) with lattice parameters: a = 7.9193(5), b = 9.4907(6), c = 8.8090(6) Å, β = 95.180(2)°, Z = 4 for RbFe(SO₄)(C₂O₄)_0.5 · H₂O; a = 8.0654(11), b = 9.6103(13), c = 9.2189(13) Å, β = 94.564(4)°, Z = 4 for CsMn(SO₄)(C₂O₄)_0.5 · H₂O; and a = 7.9377(3), b = 9.5757(4), c = 9.1474(4) Å, β = 96.1040(10)°, Z = 4 for CsFe(SO₄)(C₂O₄)_0.5 · H₂O. All compounds exhibit three‐dimensional frameworks composed of [MO₆] octahedra, [SO₄]^2– tetrahedra, and [C₂O₄]^2– anions. The alkali cations are located in one‐dimensional tunnels.     

Reactions with Oleum under Harsh Conditions: Characterization of the Unique [M(S2O7)3]2− Ions (M=Si,Ge, Sn) in A2[M(S2O7)3] (A=NH4, Ag)

The reactions of group 14 tetrachlorides MCl₄ (M=Si, Ge, Sn) with oleum (65 % SO₃) at elevated temperatures lead to the unique complex ions [M(S₂O₇)₃]^2?, which show the central M atoms in coordination with three chelating S₂O₇^2? groups. The mean distances M? O within the anions increase from 175.6(2)–177.5(2) pm (M=Si) to 186.4(4)–187.7(4) pm (M=Ge) to 201.9(2)–203.5(2) pm (M=Sn). These distances are reproduced well by DFT calculations. The same calculations show an increasing positive charge for the central M atom in the row Si, Ge, Sn, which can be interpreted as the decreasing covalency of the M? O bonds. For the silicon compound (NH₄)₂[Si(S₂O₇)₃], ²⁹Si solid‐state NMR measurements have been performed, with the results showing a signal at ?215.5 ppm for (NH₄)₂[Si(S₂O₇)₃], which is in very good agreement with theoretical estimations. In addition, the vibrational modes within the [MO₆] skeleton have been monitored by Raman spectroscopy for selected examples, and are well reproduced by theory. The charge balance for the [M(S₂O₇)₃]^2? ions is achieved by monovalent A⁺ counter ions (A=NH₄, Ag), which are implemented in the syntheses in the form of their sulfates. The sizes of the A⁺ ions, that is, their coordination requirements, cause the crystallographic differences in the crystal structures, although the complex [M(S₂O₇)₃]^2? ions remain essentially unaffected with the different A⁺ ions. Furthermore, the nature of the A⁺ ions influences the thermal behavior of the compounds, which has been monitored for selected examples by thermogravimetric differential thermal analysis (DTA/TG) and XRD measurements.     

Chemical Bonding in Homoleptic Carbonyl Cations [M{Fe(CO)5}2]+ (M=Cu,Ag, Au)

Syntheses of the copper and gold complexes [Cu{Fe(CO)₅}₂][SbF₆] and [Au{Fe(CO)₅}₂][HOB{3,5-(CF₃)₂C₆H₃}₃] containing the homoleptic carbonyl cations [M{Fe(CO)₅}₂]⁺ (M=Cu, Au) are reported. Structural data of the rare, trimetallic Cu₂Fe, Ag₂Fe and Au₂Fe complexes [Cu{Fe(CO)₅}₂][SbF₆], [Ag{Fe(CO)₅}₂][SbF₆] and [Au{Fe(CO)₅}₂][HOB{3,5-(CF₃)₂C₆H₃}₃] are also given. The silver and gold cations [M{Fe(CO)₅}₂]⁺ (M=Ag, Au) possess a nearly linear Fe-M-Fe’ moiety but the Fe-Cu-Fe’ in [Cu{Fe(CO)₅}₂][SbF₆] exhibits a significant bending angle of 147° due to the strong interaction with the [SbF₆]⁻ anion. The Fe(CO)₅ ligands adopt a distorted square-pyramidal geometry in the cations [M{Fe(CO)₅}₂]⁺, with the basal CO groups inclined towards M. The geometry optimization with DFT methods of the cations [M{Fe(CO)₅}₂]⁺ (M=Cu, Ag, Au) gives equilibrium structures with linear Fe-M-Fe’ fragments and D₂ symmetry for the copper and silver cations and D_4d symmetry for the gold cation. There is nearly free rotation of the Fe(CO)₅ ligands around the Fe-M-Fe’ axis. The calculated bond dissociation energies for the loss of both Fe(CO)₅ ligands from the cations [M{Fe(CO)₅}₂]⁺ show the order M=Au (D_e=137.2 kcal mol⁻¹)>Cu (D_e=109.0 kcal mol⁻¹)>Ag (D_e=92.4 kcal mol⁻¹). The QTAIM analysis shows bond paths and bond critical points for the M−Fe linkage but not between M and the CO ligands. The EDA-NOCV calculations suggest that the [Fe(CO)₅]→M⁺←[Fe(CO)₅] donation is significantly stronger than the [Fe(CO)₅]←M⁺→[Fe(CO)₅] backdonation. Inspection of the pairwise orbital interactions identifies four contributions for the charge donation of the Fe(CO)₅ ligands into the vacant (n)s and (n)p AOs of M⁺ and five components for the backdonation from the occupied (n-1)d AOs of M⁺ into vacant ligand orbitals.     

Electrochemiluminescent Determination of Chlorphenamine Maleate Based on Ru(bpy)$\rm{ {_{3}^{2+}}}$ Immobilized in a Nano‐Titania/Nafion Membrane

The immobilization of tris(2,2'‐bipyridyl)ruthenium(II) [Ru(bpy) ] in a TiO₂/Nafion nanocomposites membrane modified glassy carbon electrode (GCE) was achieved via both an ion‐exchange process and hydrophobic interactions .The surface‐confined Ru(bpy) shows good electrochemical and photochemical activities. The Ru(bpy) underwent reversible surface process and reacted with chlorphenamine maleate (CPM) to produce electrochemiluminescence. The modified electrode was used for the ECL determination of CPM. It showed good linearity in the concentration range from 2×10^?8 g/mL to 1×10^?6 g/mL (R=0.9995) with a detection 6×10^?9 g/mL (S/N=3). The relative standard derivation (n=11) was 2%. This method is developed for the determination of CPM with simplicity and high sensitivity.     

Synthesis and Characterization of 1,3,2‐Bis (arylamino) phospholidine, 2‐oxide Derivatives: Crystal Structures of $\rm Cl(O)\overline{PN(p-Me-C_{6}H_{4})CH_{2}CH_{2}N}(p-Me-C_{6}H_{4})$ and $\rm ((CH_{2}C_{6}H_{5})(O)\overline{PN(p-Me-C_{6}H_{4})CH_{2}CH_{2}N}(p-Me-C_{6}H_{4})$

Using phosphoryl chloride as a substrate, a family of 1,3,2‐bis(arylamino) phospholidine, 2‐oxide of the general formula ; (X=Cl, 6a ; X=NMe₂, 1b ; X=N(CH₂C₆H₅)(CH₃), 2b ; X=NHC(O)C₆H₅, 3b ; X=4Me‐C₆H₄O, 4b ; X=C₆H₅O, 5b ; X=NHC₆H₁₁, 6b ; X=OC₄H₈N, 7b ; X=C₅H₁₀N, 8b ; X=NH₂, 9b ; X=F, 10b and Ar=4Me‐C₆H₄) was prepared and characterized by ¹H, ¹⁹F, ³¹P and ¹³C NMR and IR spectroscopy, and elemental analysis. A general and practical method for the synthesis of these compounds was selected. The structures of 6a and 2b were determined by single‐crystal X‐ray diffraction techniques. The low temperature NMR spectra of 2b revealed the restricted rotation of P‐N bond according to two independent molecules in crystalline lattice.     

K2M(H2P2O7)2·2H2O (M = Ni,Cu, Zn): ortho­rhom­bic forms and Raman spectra

The crystal structures of three isotypic ortho­rhom­bic dihydrogendiphosphates, namely dipotassium copper(II)/nickel(II)/zinc(II) bis­(dihydrogendiphosphate) dihydrate, K₂M(H₂P₂O₇)₂·2H₂O (M = Cu, Ni and Zn), have been refined from single‐crystal data. The M²⁺ and K⁺ cations are located at sites of m symmetry, and the P atoms occupy general positions. These compounds also exist in triclinic forms with very similar structural features. The structures of both forms are compared, as well as the geometry of the MO₆ octa­hedron, which is considerably elongated towards the water mol­ecules for M = Ni and Cu. Such elongation has not been observed among the other representatives of the family. A Raman study of the whole series K₂M(H₂P₂O₇)₂·2H₂O (M = Mn, Co, Ni, Cu, Zn and Mg) is reported.     

Electrochemical Detection of ClO$\rm{ {_{3}^{-}}}$, BrO$\rm{ {_{3}^{-}}}$, and IO$\rm{ {_{3}^{-}}}$ at a Phosphomolybdic Acid Linked 3‐Aminopropyl‐Trimethoxysilane Modified Electrode

A composite film modified electrode containing a Keggin‐type heteropolyanion, H₃(PMo₁₂O₄₀)?H₂O, was fabricated with 3‐aminopropyltrimethoxysilane (APMS) attached on an electrochemically activated glassy carbon (GC) electrode through the formation of C? O? Si bond. PMo₁₂O was then complexed with APMS through the electrostatic interaction between the phosphate groups of PMo₁₂O and amine groups of APMS (PMo₁₂O ‐APMS). XPS and cyclic voltammetry were employed for characterization of the composite film. The PMo₁₂O ‐APMS modified electrode showed three reversible redox pairs with smaller peak‐separation and was stable in the larger pH range compared with that in a solution phase. The catalytic properties of the modified electrode for the reduction of ClO , BrO , and IO were studied and the modified electrode exhibited good electrocatalytic activities for the three anions. The experimental parameters, such as pH, temperature, and the applied potential were optimized. The detection limits were determined to be 7.0±0.35 μM, 4.0±0.17 μM, and 0.1±0.04 μM for ClO , BrO , and IO , respectively. The modified electrode was applied to natural water samples for the detection of ClO , BrO , and IO .     

On the Interchange Ability of the N‐donor Position in the Rare Earth Coordination Polymers $^{1}_{\infty}\rm [Ln(Btz)_{3}(L)]$, L = BtzH,Ph(NH2)2, NH3, and Pyridine

Benzotriazolates of the rare earth elements form chain like coordination polymers of the formula . An additional neutral ligand L saturates the coordination spheres of the trivalent lanthanide ions and, depending on the reaction conditions, can be a varying donor (L = BtzH, Ph(NH₂)₂, NH₃ and Py). Reactions in the BtzH (1H‐benzotriazole) melt result in coordination of benzotriazole and its thermal decomposition products as L. We have now investigated if the site occupied by L can be exchanged with other N donor ligands. Pyridine can substitute BtzH, Ph(NH₂)₂ and NH₃ under solvothermal conditions giving the coordination polymer even for the biggest Ln^III cation lanthanum without changing the overall strand structure. Chains proof to be the chemically favoured and stable structure fragment with the L position being the chemically variable site.