Enantiopure Chiral Macrocyclic Lanthanide Complexes Derived from (R)-2,2′-Diamino-1,1′-binaphthyl and 2,6-Diformylpyridine

The template condensation of (R)-2,2′-diamino-1,1′-binaphthyl and 2,6-diformylpyridine leads to lanthanide(III) complexes of the new chiral hexaaza macrocycle L that adopts highly twisted conformation in [LnL](NO₃)₃ complexes. The complexes have been characterised by ESI MS spectrometry and NMR spectroscopy. The analogous N₂O₄ chiral crown ether L2 that has the same carbon skeleton as L does not exhibit tendency to bind lanthanide(III) ions. The X-ray crystal structure of L2 exhibit squeezed conformation of the macrocycle and spatial disposition of donor atoms that does not predispose it for coordination of lanthanide(III) ions.     

Syntheses and Crystal Structures of Potassium–Lanthanoid(III) Complexes with the 1,2‐Benzenedisulfonate Ligand

The complexes [K(H₂O)₂LnL₂] (Ln = La or Nd; L = 1,2‐benzenedisulfonate) and [K(H₂O)Yb(H₂O)₄L₂] were initially isolated fortuitously from attempts to prepare the corresponding Ln₂L₃ complexes from Ln₂O₃ and H₂L in water. Indeed the bulk products from these reactions have the composition Ln₂L₃. Subsequently, deliberate syntheses by reacting equimolar amounts of Ln₂L₃ with K₂L in water gave the complexes in good yield. X‐ray crystal structures of [K(H₂O)₂LnL₂] (Ln = La or Nd) showed the complexes to be isostructural with a two dimensional polymeric network structure in which LnL₂ units are linked into chains crosslinked by potassium ions. Each Ln is nine coordinate with solely sulfonate oxygen donor atoms. Between adjacent lanthanoid ions there are three different types of sulfonate bridges and two examples of each. Most noteworthy is highly unsymmetrical bridging through μ‐η²‐sulfonate oxygen atoms. Consequently, one Ln–O bond is ca. 0.5 Å longer than the other eight. Potassium is nine‐coordinate with seven sulfonate oxygen atoms and two aqua ligands, and surprisingly <K–O(sulfonate)> is much longer than <K–O(H₂O)>. Pairs of potassium ions are linked by two μ‐η²‐sulfonate oxygen atoms, which are unsymmetrically bridging. The structure of [K(H₂O)Yb(H₂O)₄L₂] comprises discrete tetranuclear units containing two independent ytterbium ions, each coordinated by four water molecules and two chelating (via seven membered rings) disulfonate ligands, and two potassium ions, each coordinated by six sulfonate oxygen atoms and a water molecule. For each potassium, four of the coordinated sulfonate oxygen atoms are from sulfonate ligands bonded to one ytterbium atom and two from sulfonate ligands attached to the other ytterbium atom. In contrast to the Nd and La complexes, <K–O(sulfonate)> is shorter than <K–O(H₂O)>.     

Ethylene polymerization with imine and phosphine nickel complexes containing isothiocyanate

Three isothiocyanate complexes of nickel(II) containing diimine [ArN?C(Me)? C(Me)?NAr]Ni‐ (NCS)₂ (1), iminophosphine [Ph₂PC₆H₄CH?NAr]Ni(NCS)₂ (2), or diphosphine (dppe)Ni(NCS)₂ (3), [Ar = 2, 6‐ⁱPr‐C₆H₃; dppe = 1, 2‐bis(diphenylphosphine)ethane] were synthesized and examined for ethylene polymerization activated by methylaluminoxane (MAO). Their behavior was compared with those of the corresponding halide analogues [ArN?C(Me)? C(Me)?NAr]NiBr₂ (4), [Ph₂PC₆H₄CH?NAr]NiBr₂ (5), and (dppe)NiCl₂ (6). The diimines showed the highest polymerization activity. Replacement of the halide for the NCS pseudo halide affected the activity and decreased the molecular weight of the polymer formed. The highest molecular weights were obtained with the diimine complexes. Highly branched polyethylenes were obtained with the bulkier complexes 1 and 4. Replacement of the halide for NCS in the diimine complexes also caused an increase in the branching content, whereas the opposite occurs for the iminophosphine complexes. The different activities and behavior of the catalyst systems with halide versus NCS in the polymerization of ethylene and the characteristics of the final products suggest a modification in the active species caused by the non‐chelating ligand. Polymer molecular weight and branching content is dependent on the MAO/Ni molar ratio and on the working temperature. Copyright © 2004 John Wiley & Sons, Ltd.     

New Luminescent Lanthanide Tetrakis-Complexes NEt4[LnL4] Based on Dimethyl-N-Benzoylamidophosphate

New lanthanide dimethyl-N-benzoylamidophosphate (HL) based tetrakis-complexes NEt₄[LnL₄] (Ln³⁺=La, Nd, Sm, Eu, Gd, Tb, Dy) are reported. The complexes are characterized by means of NMR, IR, absorption, and luminescent spectroscopy as well as by elemental, X-Ray, and thermal gravimetric analyses. The phenyl groups of the four ligands of the complex anion are directed towards one side, while the methoxy groups are directed in the opposite side, which makes the complexes under consideration structurally similar to calixarenes. The effect of changing the alkali metal counterion to the organic cation NEt₄⁺ on the structure and properties of the tetrakis-complex [LnL4]^- is analyzed. The complexes exhibit bright characteristic for respective lanthanides luminescence. Rather high intensity of the band of ⁵D₀→⁷F₄ transition, observed in the luminescence spectrum of NEt₄[EuL₄], is discussed based on theoretical calculations.     

Synthesis,crystal structures and magnetism of lanthanide(III) binuclear complexes [Ln2(μ1 ,3-CH3CO2)2(SCN−)4L2(H2O)6] (Ln = Gd(III) and Eu(III), L = 4-methylpyridine N-oxide)

Two lanthanide(III) binuclear complexes have been synthesized with acetate as bridging ligand and 4-methylpyridine N-oxide (L), SCN^? and H₂O as terminal ligands and structurally determined by X-ray crystallography. Both crystals [Gd₂(μ_1,3-CH₃CO₂)₂(SCN^?)₄(L)₂(H₂O₆) (1) and [Eu₂(μ_1,3-CH₃CO₂)₂(SCN^?)₄(L)₂(H₂O)₆] (2) belong to monoclinic with space group P2₁/n. The relevant cell parameters are as follows: a?=?9.0034(12)?Å, b?=?15.998(2)?Å, c?=?12.1277(17)?Å, β?=?100.625(2)° for complex 1; and a?=?9.0168(18)?Å, b?=?15.990(3)?Å, c?=?12.142(2)?Å, β?=?100.734(3)° for complex 2; The two lanthanide(III) ions are bridged by two acetate anions forming a binuclear unit, in which L, SCN^? and H₂O as unidentate terminal ligands take part in the coordination. The variable-temperature magnetic susceptibility of 1 was measured in the 4–300?K range; fitting for the susceptibility data reveals that there is no magnetic interaction between the bridged Gd(III) ions.     

Synthesis and characterization of the organoimidopolyoxomolybdates [ n -Bu4N]2[Mo6O17(≡NAr)2] (Ar = 2-ethyl-6-methylphenyl and 2-isopropyl-6-methylphenyl)

Two new bifunctionalized arylimido derivatives of hexamolybdate, [n-Bu₄N]₂[Mo₆O₁₇(C₆H₃N-2-C₂H₅-6-CH₃)₂] (1) and [n-Bu₄N]₂[Mo₆O₁₇(C₆H₃N-2-CH(CH₃)₂-6-CH₃)₂]?·?H₂O (2), in which the two organoimido groups are covalently bonded to hexamolybdate at the cis positions, were synthesized by self-assembled metathesis of α-octamolybdate and organoimido ligands with N,N′-dicyclohexylcarbodiimide as dehydration agent, and characterized by elemental analysis, ¹H NMR, IR and electronic spectroscopy, and X-ray diffraction analysis. Both derivatives have short Mo–N bond distances [Mo(1)–N(1), 1.740(3)?Å; Mo(2)–N(2), 1.739(3)?Å for 1 and Mo(1)–N(1), 1.734(3)?Å; Mo(2)–N(2), 1.741(3)?Å for 2] and form dimers via π–π stacking in the crystalline state.     

以1，4-二硝基苯甲酸及邻菲啰啉为配位的镧系金属配位聚合物的合成、结构及性质研究

以1,4-二硝基苯甲酸（HL）和1,10-邻菲罗啉（phen）为配体,通过水热法与镧系金属盐合成了7个一维链状配位聚合物,其分子式为[Ce₂L₆（phen）₂]_n（1）和[LnL₃phen]_n（Ln=Sm,2;Eu,3;Gd,4;Tb,5;Dy,6;Er,7）。由X-射线单晶衍射测定了化合物晶体结构,通过磁性以及荧光测试表征了部分化合物的磁性和荧光性质。     

Copolymerization of carbon dioxide and cyclohexene oxide with zinc/β‐ketoiminato complexes: Investigating the influence of the electron structure of zinc/β‐ketoiminato complexes on the catalytic activity and resultant copolymer properties

A series of LZnX zinc/β‐ketoiminato complexes [L = CH₃C(OH)?C(CH₂CH?CH₂)C(CH₃)?NAr ( L₁ ), CH₃C(OH)?C(CH₂CH₂CN)C(CH₃)?NAr ( L₂ ), CH₃C(OH)?C(CH₂C₆H₅)C(CH₃)?NAr ( L₃ ), or CH₃C(OH)?CHC(CH₃)?NAr ( L₄ ); Ar = 2,6‐ⁱPr₂C₆H₃; and initiation group X = alcoholate or acetate (for L₁ ) or alcoholate (for L₂ – L₄ )] were synthesized, and their activities toward the copolymerization of carbon dioxide with cyclohexene oxide were determined. The 3‐position substituents on the β‐ketoiminato ligand backbone of the zinc/β‐ketoiminato complexes played an important role not only in the catalytic activity but also in the intrinsic viscosity, chemical composition, and refined microstructure of the resultant copolymers. The order of the catalytic activity of L₁ ZnX with different initiation groups (X = OMe, OⁱPr, or OAc) was L₁ Zn (OⁱPr) > L₁ Zn (OMe) > L₁ Zn (OAc), being the opposite of the order of the leaving ability of the initiation groups. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6243–6251, 2006     

Crystal structures of two Ca(II) complexes with imidazole-4,5-dicarboxylate and water ligands

The structure of compound I: poly-diaqua(μ-imidazole-4,5-dicarboxylato-N,O; -O′; -O′′, -O′′′) calcium(II) monohydrate [Ca(C₅H₂N₂O₄)(H₂O)₂·H₂O] is built of molecular sheets in which imidazole-4,5-dicarboxylate ligands bridge the metal ions using both carboxylate groups, each bidentate. Ca(II) is coordinated by six oxygen atoms and one hetero-ring nitrogen atom distributed at the apices of a capped tetragonal bipyramid. The basal plane of the pyramid is formed by two carboxylate oxygen atoms [d(Ca–O2?=?2.374(1)?Å, d(Ca–O4)?=?2.412(1)?Å] and two water oxygen atoms [d(Ca–O5)?=?2.384(1)?Å, d(Ca–O6)?=?2.455(1)?Å], the capped position is occupied by the carboxylate oxygen atom O3 [d(Ca–O3)?=?2.325(1)?Å], the hetero-ring nitrogen atom [d(Ca–N2)?=?2.523(1)?Å] and the carboxylate oxygen atom O4 [d(Ca–O2)?= 2.412(1)?Å] form the apices of the prism. The solvation water molecule plays a significant role in a framework of hydrogen bonds responsible for the stability of the crystal. The structure of compound II: trans-tetraquadi(H-imidazole-4,5-dicarboxylato-N,O) calcium(II) monohydrate, [Ca(C₅H₃N₂O₄)₂(H₂O)₄·H₂O] consists of monomers in which the Ca(II) ion is located on a centre of symmetry. The coordination around the Ca(II) is a strongly deformed pentagonal bipyramidal with the imidazole-4,5-dicarboxylate (4,5-IDA) ligands in the trans arrangement forming a dihedral angle of 68.3°. An imidazole-ring nitrogen atom [d(Ca–N)?=?2.632(2)?Å] and one carboxylate O atom [d(Ca–O)?=?2.531(2)?Å] from each ligand coordinate to the metal ion. The coordination is completed by four water oxygen atoms [d(Ca–O)?=?2.393(2)?Å] and [d(Ca–O)?=?2.367(2)?Å]. The coordinated water molecules act as hydrogen bond donors and acceptors to the unbonded carboxylate oxygen atoms in adjacent monomers giving rise to a three-dimensional molecular network.     

Lanthanide(III) Nitrate Complexes of Two 17 Membered N3O2-Donor Macrocycles

The interaction of lanthanide(III) ions with two N₃O₃-macrocycles, L¹ and L², derived from 2,6-bis(2-formylphenoxymethyl)pyridine and 1,2-diaminoethane has been investigated. Schiff-base macrocyclic lanthanide(III) complexes LnL¹(NO₃)₃ · xH₂O (Ln = Nd, Sm, Eu or Lu) have been prepared by direct reaction of L¹ and the appropriate hydrated lanthanide nitrate. The direct reaction between the diamine macrocycle L² and the hydrated lanthanide(III) nitrates yields complexes LnL²(NO₃)₃· H₂O only for Ln = Dy or Lu. The reduction of the Schiff-base macrocycle decreases the complexation capacity of the ligand towards the Ln(III) ions. The complexes have been characterised by elemental analysis, molar conductivity data, FAB mass spectrometry, IR and, in the case of the lutetium complexes, ¹H NMR spectroscopy.     

Synthesis,crystal structure,and magnetic properties of a salt containing [Cu2Cl7]3− and 4-nitrobenzyl-4′-dimethylaminopyridinium

A new salt, [NO₂BzDMAP]₃[Cu₂Cl₇]?·?H₂O (1), has been synthesized, where [NO₂BzDMAP]⁺ is 1-(4′-nitrobenzyl)-4-dimethylaminopyridinium. Herein, the synthesis, spectral and structural characterization, and magnetic behavior of 1 are reported. It is orthorhombic, with space group Pca2₁, and a?=?26.639(2)?Å, b?=?9.638(1)?Å, and c?=?20.011(2)?Å with V?=?5137.5(7)?ų for Z?=?4. The anion shows a chloride-bridged binuclear structure with Cu?···?Cu distance of 3.872?Å; the two Cu(II) ions have a tetrahedral geometry. The cations stack through p?···?π and π?···?π interactions, and a complicated hydrogen-bonding network structure is formed through C–H?···?Cl and C–H?···?O hydrogen bonds. The variable temperature magnetic susceptibility measurements reveal that 1 exhibits strong antiferromagnetic interaction with J?=??193.0?cm^?1.     

Copper Coordination Polymers of N1,N4-Bis(pyridin-2-ylmethyl)terephthalamide: Synthesis,Structures, DNA Binding and Cleavage,and Catalytic Activity for Oxidation of 1-Phenylethanol

Two Cu coordination polymers [Cu(bpmt)Cl₂ · 2DMF]_n ( 1 ), [Cu(bpmt)(μ-Cl) · DMSO]_n ( 2 ) [bpmt = N¹,N⁴-bis(pyridin-2-ylmethyl)terephthalamide)], were synthesized and characterized. X-ray single-crystal diffractions revealed complex 1 exhibits a one-dimensional (1D) chain in which central Cu^II ions are located in a six-coordinate slightly distorted octahedral structure. Complex 2 features 1D chain composed of Cu^I–Cl bridges and all the central Cu^I ions are situated a twisted tetrahedral configurations. Multi-spectroscopic DNA interaction studies indicate that the two complexes may bind to DNA via groove binding modes, and the calculated binding constants are 1.42 × 10⁴ ( 1 -CT-DNA) and 1.41 × 10⁴ ( 2 -CT-DNA). Both complexes are also capable of efficiently cleaving plasmid pBR322 DNA in the presence of H₂O₂ via an oxidative mechanism. Furthermore, 1 and 2 are employed as catalysts for the oxidation of 1-phenylethanol to acetophenone. Complex 1 displays good catalytic potential with the conversion rate reaches 99 % using tert-butyl hydroperoxide (TBHP) as oxidant and CH₃CN as solvent at 60 °C for 2.0 h.     

Transition-metal complexes with bidentate ligands spanning trans-position. Part XVI. X-ray structural and 31P-NMR solution studies of 2,11-Bis(diethylphosphinomethyl)benzo[c]phenanthrenesilver(I) perchlorate

The preparation of complexes {AgX(1c)} (X ? Cl, Br, I, NO₃ and ClO₄; 1c = 2,11-bis(diethylphosphinomethyl)benzo[c]phenanthrene) is reported. The ³¹P-NMR spectra of the above complexes were recorded and the ¹J(¹⁰⁷Ag, ³¹P) values are compared with the corresponding data for related complexes. The X-ray crystal structure of [Ag(1c)](ClO₄) was determined. There are two crystallographically independent molecules in the unit cell each containing two-coordinate silver, the O-atoms of the perchlorate anions being outside bonding range from the central atom. The two molecules, however, show different bonding parameters: Thus for ‘molecule 1’ P(1)? Ag(1)? P(2) = 167.6(1)°, Ag(1)? P(1) = 2.389(3) and Ag(1)? P(2) = 2.393(3) Å, while for ‘molecule 2’ P(3)? Ag(2)? P(4) = 164.8(1)°, Ag(2)? P(3) = 2.377(3), and Ag(2)? P(4) = 2.378(3) Å. These differences are probably due to packing forces in the crystal lattice.     

The energy surface for isomeric [C2H3O]+ ions: Further experimental evidence

Mass spectra from collisionally activated dissociation (CAD) of [C₂H₃O]⁺ ions, including isotopically labeled analogs, provide further information on the isomers [CH₃C?O⁺] (a), [CH₂?C?O⁺H] (b), [⁺CH₂CH?O] (c) and (d). Our data generally support the recent conclusions from theory by Radom and coworkers and from experiment by Terlouw, Holmes and coworkers. Most acetyl-containing molecular ions form a ions in high purity only at low energies, consistent with isomerization of higher energy molecular ions to form the more stable enol which dissociates to b. Isomer d, prepared from (CICH₂)₂CHOH, undergoes facile hydrogen scrambling, presumably through a degenerate 1,2-hydrogen shift. Theory suggests that c undergoes spontaneous isomerization to a and d; although [C₂H₃O]⁺ ions from BrCH₂CHO appear to consist of a and ～15% d, the latter are formed without substantial hydrogen scrambling.     

Characterization and spectroscopic study of new complexes of Cd(II), Hg(II) and Pb(II) with the sodium salt of morin-5′-sulfonic acid

Solid compounds of Cd(II), Hg(II) and Pb(II) with the sodium salt of morin-5′-sulfonic acid (NaMSA) were obtained. The molecular formula of the complexes are: Cd(C₁₅H₈O₁₀SNa)₂?·?6H₂O, CdOH(C₁₅H₈O₁₀SNa)?·?4H₂O, Hg(C₁₅H₈O₁₀S)?·?4H₂O and Pb(C₁₅H₈O₁₀S)?·?3H₂O. Some of their physicochemical properties such as UV-Vis, infrared, ¹³C NMR and mass spectra, thermogravimetric analysis, and solubility were studied. On the basis of spectroscopic data NaMSA was bound to Cd²⁺ via 4C=O and 3C?–?oxygen and the Hg²⁺ and Pb²⁺ ions by 5C–OH, 4C=O and 3C–OH.     

Nitro‐substituted iron(II) tridentate bis(imino)pyridine complexes as high‐temperature catalysts for the production of α‐olefins

A new series of nitro‐substituted bis(imino)pyridine ligands {2,6‐bis[1‐(2‐methyl‐4‐nitrophenylimino)ethyl]pyridine, 2,6‐bis[1‐(4‐nitrophenylimino)ethyl]pyridine, (1‐{6‐[1‐(4‐nitro‐phenylimino)‐ethyl]‐pyridin‐2‐yl}‐ethylidene)‐(2,4,6‐trimethyl‐phenyl)‐amine, and 2,6‐bis[1‐(2‐methyl‐3‐nitrophenylimino)ethyl]pyridine} and their corresponding Fe(II) complexes [{p‐NO₂? o‐Me? Ph? N?C(Me)? Py? C(Me)?N? Ph? o‐ Me? p‐NO₂}FeCl₂ ( 10 ), L₂FeCl₂ ( 11 ), {m‐NO₂? o‐Me? Ph? N?C(Me)? Py? C(Me)?N? Ph? o‐Me? m‐NO₂}FeCl₂ ( 12 ), and {p‐NO₂? Ph? N?C(Me)? Py? C(Me)?N? Mes}FeCl₂ ( 14 )] were synthesized. According to X‐ray analysis, there were shortenings of the axial Fe? N bond lengths (up to 0.014 Å) in para‐nitro‐substituted complex 10 and (up to 0.015 Å) in meta‐nitro‐substituted complex 12 versus the Fe(II) complex without nitro groups [{o‐Me? Ph? N?C(Me)? Py? C(Me)?N? Ph? o‐Me}FeCl₂ ( 1 )]. Complexes 10 , 12 , and 14 afforded very active catalysts for the production of α‐olefins and were more temperature‐stable and had longer lifetimes than parent non‐nitro‐substituted Fe(II) complex 1 . The reaction between FeCl₂ and a sterically less hindered ligand [p‐NO₂? Ph? N?C(Me)? Py? C(Me)?N? Ph? p‐NO₂] resulted in the formation of octahedral complex 11 . A para‐dialkylamino‐substituted bis(imino)pyridine ligand [p‐NEt₂? o‐Me? Ph? N?C(Me)? Py? C(Me)?N? Ph? o‐Me? p‐NEt₂] and the corresponding Fe(II) complex [{p‐NEt₂? o‐Me? Ph? N?C(Me)? Py? C(Me)?N? Ph? o‐Me? p‐NEt₂}FeCl₂ ( 16 )] were synthesized to evaluate the effect of enhanced electron donation of the ligand on the catalytic performance. According to X‐ray analysis, there was a shortening (up to 0.043 Å) of the axial Fe? N bond lengths in para‐diethylamino‐substituted complex 16 in comparison with parent Fe(II) complex 1 . © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2615–2635, 2006     

以1,4-二硝基苯甲酸及邻菲咯啉为配位的镧系金属配位聚合物的合成、结构及性质研究

以1,4-二硝基苯甲酸(HL)和1,10-邻菲咯啉(phen)为配体,通过水热法与镧系金属盐合成了7个一维链状配位聚合物,其分子式为[Ce2L6(phen)2]n(1)和[LnL3phen]n(Ln=Sm,2;Eu,3;Gd,4;Tb,5;Dy,6;Er,7)。由X-射线单晶衍射测定了化合物晶体结构,通过磁性以及荧光测试表征了部分化合物的磁性和荧光性质。     

Synthesis and Structural Characterization of β‐Ketoiminate‐Stabilized Gallium Hydrides for Chemical Vapor Deposition Applications

Bis‐β‐ketoimine ligands of the form [(CH₂)_n{N(H)C(Me)?CHC(Me)?O}₂] (LⁿH₂, n=2, 3 and 4) were employed in the formation of a range of gallium complexes [Ga(Lⁿ)X] (X=Cl, Me, H), which were characterised by NMR spectroscopy, mass spectrometry and single‐crystal X‐ray diffraction analysis. The β‐ketoimine ligands have also been used for the stabilisation of rare gallium hydride species [Ga(Lⁿ)H] (n=2 ( 7 ); n=3 ( 8 )), which have been structurally characterised for the first time, confirming the formation of five‐coordinate, monomeric species. The stability of these hydrides has been probed through thermal analysis, revealing stability at temperatures in excess of 200 °C. The efficacy of all the gallium β‐ketoiminate complexes as molecular precursors for the deposition of gallium oxide thin films by chemical vapour deposition (CVD) has been investigated through thermogravimetric analysis and deposition studies, with the best results being found for a bimetallic gallium methyl complex [L³{GaMe₂}₂] ( 5 ) and the hydride [Ga(L³)H] ( 8 ). The resulting films ( F5 and F8 , respectively) were amorphous as‐deposited and thus were characterised primarily by XPS, EDXA and SEM techniques, which showed the formation of stoichiometric ( F5 ) and oxygen‐deficient ( F8 ) Ga₂O₃ thin films.     

Reactivity of Dialumane and “Dialumene” Compounds toward Alkenes

The reactions of dialumane [L(thf)Al? Al(thf)L] ( 1 , L=[{(2,6‐iPr₂C₆H₃)NC(Me)}₂]^2?) with stilbene and styrene afforded the oxidation/insertion products [L(thf)Al(CH(Ph)? CH(Ph))AlL] ( 2 ) and [L(thf)Al(CH(Ph)? CH₂)Al(thf)L] ( 3 ), respectively. In the presence of Na metal, precursor 1 reacted with butadienes, possibly through the reduced “dialumene” or the “carbene‐like” :AlL species, to yield aluminacyclopentenes [LAl(CH₂C(Me)?C(Me)CH₂)Na]_n ( 4 a ) and [Na(dme)₃][LAl(CH₂C(Me)?CHCH₂)] ( 4 b , dme=dimethoxyethane) as [1+4] cycloaddition products, as well as the [2+4] cycloaddition product 1,6‐dialumina‐3,8‐cyclodecadiene, [{Na(dme)}₂][LAl(CH₂C(Me)?C(Me)CH₂)₂AlL] ( 5 ). The possible mechanisms of the cycloaddition reactions were studied by using DFT computations.     

K⋅⋅⋅F/O Interactions Bridge Copper(I) Fluorinated Alkoxide Complexes and Facilitate Dioxygen Activation

Seven E[Cu(OR)₂] copper(I) complexes (E=K⁺, {K(18C6)}⁺ (18C6=[18]crown‐6), or Ph₄P⁺; R=C₄F₉, CPhMe^F₂, and CMeMe^F₂) have been prepared and their reactivity with O₂ studied. The K[Cu(OR)₂] species react with O₂ in a copper‐concentration‐dependent manner such that 2:1 and 3:1 Cu/O₂ adducts are observed manometrically at ?78 °C. Analogous reactivity with O₂ is not observed with the {K(18C6)}⁺ or Ph₄P⁺ derivatives. Solution conductivity data demonstrate that these K[Cu(OR)₂] complexes do not behave as 1:1 electrolytes in solution. The K⁺ ions induce aggregation of multiple [Cu(OR)₂]^? units through K???F/O interactions and thereby effect irreversible O₂ reduction by multiple Cu centers. Bond valence analyses for the potassium cations confirm the dominance of the fluorine interactions in the coordination spheres of K⁺ ions. Intramolecular hydroxylation of ligand aryl and alkyl C? H bonds is observed. Nucleophilic reactivity with CO₂ is observed for the oxygenated Cu complexes and a Cu^II carbonate has been isolated and characterized.