Metal Template Reactions Research Articles

Solid state photoluminescence studies of [EuLnH2(NO3)3](H2O)x macrocyclic complexes with Schiff base ligands

Three EuIII macrocyclic complexes [EuLnH2(NO3)3](H2O)x based on the ligands derived from 2-hydroxy-5-methyl-1,3-benzenedicarbaldehyde and three different amines: o-phenylenediamine, Eu-OPDA; ethylenediamine, Eu-EDA; and 1,3-diaminopropane, Eu-DAP have been synthesized via a metal template reaction. Eu-EDA and Eu-DAP showed metal based emission; for the Eu-OPDA complex these luminescent properties were not observed. From the photoluminescence emission measurements from ~13 to 300 K, the R/O = I (5D0 → 7F2)/I (5D0 → 7F1) ratio, together with two intensity parameters (Ω2 and Ω4), radiative lifetimes (τR) and branching ratios (β0 J′) were calculated based on the Judd-Ofelt theory, for Eu-EDA and Eu-DAP. While the behavior of these parameters for the Eu-DAP complex is temperature dependent, these remain constant for Eu-EDA. The temperature dependence observed for the Eu-DAP complex indicates that for temperatures below 120 K, the local symmetry of the EuIII center is modified, as compared to the environment of the same metal center at room temperature.

Self assembly of dialkoxo bridged dinuclear Fe(III) complex of pyridoxal Schiff base with C[sbnd]C bond formation – Structure, spectral and magnetic properties

The new dinuclear Fe(III) complex, [Fe2(µ-L)2]·3(H2O)·0.38(O), [L=(E)-2-(((5-(hydroxymethyl)-2-methyl-3-oxido-1κO-pyridin-4-yl)methylene)amino-1κN)-3-(3-(hydroxymethyl)-2-methyl-5-oxido-1κO-pyridin-1-ium-4-yl)-3-oxido-1:2κ2O-propanoato-2κO]∗ (∗The second ligand has swapped indices 1 and 2, denoting the individual Fe centers.), was synthesized by reaction of FeCl3·6H2O with potassium pyridoxylidenglycinate in ethanol-water solution. Pentadentate pyridoxal Schiff base ligand was generated in situ by aldol condensation of potassium pyridoxylidenglycinate and pyridoxal. A CC coupling was achieved at room temperature under metal template reaction. The complex was characterized by X-ray structural analysis at 100K, elemental analysis, spectral and magnetic measurements. The compound crystallizes in the monoclinic space group P 21/n, with unit cell parameters: a=9.7445(15)Å, b=19.489(3)Å, c=20.862(6)Å, β=92.595(17)°. Structural analysis of the complex showed that each Fe(III) center has a distorted octahedral FeNO5 core, which is sixfold coordinated through iminic nitrogen atom, two phenoxido oxygen atoms, alkoxo oxygen atom and carboxylato oxygen atom from two Schiff-base ligands forming a rhombic arrangement of metal ions and oxygen atoms. In the structure, two Fe(III) atoms are connected with two alkoxo-bridging ligands providing covalent superexchange pathway by linkage Fe1–O–Fe2 with the Fe1⋯Fe2 distance of 3.195Å. In the crystal lattice, the noncovalent interactions, hydrogen bonds, and π-π stacking interactions expand the mononuclear units to 3D supramolecular network. The temperature dependent magnetic susceptibility data (6.5–300K)indicate that the octahedral Fe(III) centers in this complex retain high-spin S=5/2 (6A1g) in the whole temperature range. The effects of zero-field splitting (D=7.67cm−1) and an antiferromagnetic coupling (J=−14.66cm−1) between the two alkoxo-oxygen bridged Fe(III) ions are discussed.

Synthesis, characterization and solid-state properties of [Zn(Hdmmthiol)2] $\cdot$ 2H2O complex

The zinc(II) complex with tridentate thiohydrazone ligand have been prepared by metal template reaction. The metal template reaction was used to prepare the zinc (II) complex with tridentate thiohydrazone ligand. The reaction of diacetylmonoxime and, morpholine N-thiohydrazidewith Zn(OAc)2 $\cdot$ 2H2O under reflux yielded the formation of the [Zn(Hdmmthiol )2] $\cdot$ 2H2O complex. The complex was characterized by a combination of protocols including elemental analysis, UV+vis, FT-IR, TG and PXRD. The temperature dependence of the electrical conductivity and the optical property of the [Zn(Hdmmthiol )2] $\cdot$ 2H2O complex is called H2dammthiol was studied. Powder X-ray diffraction (PXRD) method was used to investigate the crystal structure of the sample. The zinc complex was shown to be a member of the triclinic system. The zinc complex was determined to have n-type conductivity as demonstrated in the hot probe measurements. The complex was determined to display direct optical transition with band gaps of 2.52eV as determined by the optical absorption analysis.

Template synthesis, and X-ray crystal structures of copper(II) and nickel(II) complexes of new unsymmetrical tetradentate Schiff base ligands. Electrochemistry, antibacterial properties, and metal ion effect on hydrolysis–recondensation of the ligand

Two metal complexes, [CuII(naphsal)] (1), and [NiII(salnaph)] (2), of two new unsymmetrical tetradentate Schiff base ligands, H2naphsal {H2naphsal=N-naphthylidene-N′-salicylidene-2-aminobenzylamine} and H2salnaph {H2salnaph=N-salicylidene-N′-naphthylidene-2-aminobenzylamine} have been synthesized by metal template reaction of a tridentate Schiff base, Hnaphtabza {Hnaphtabza=N-(naphthylidene)-2-aminobenzylamine} and salicylaldehyde in the presence of the corresponding metal acetate. The dianionic naphsal2− ligand, produced in the presence of Cu(II), is a simple template condensation product, while the dianionic salnaph2− ligand, produced in the presence of Ni(II), is the hydrolytically rearranged isomer of naphsal2−. The copper(II) and nickel(II) complexes have been fully characterized and their crystal structures have been determined by single crystal X-ray diffraction. Both copper(II) and nickel(II) ions adopt a distorted square planar geometry. The cyclic voltammetric studies of 1 and 2 in acetonitrile solution showed that the CuII/CuI and NiII/NiI reduction processes are electrochemically reversible. The metal complexes were also screened for their in vitro antimicrobial activity.

A supramolecular spin crossover Fe(iii) complex and its Cr(iii) isomer: stabilization of water–chloride cluster within supramolecular host

The metal complexes, [M(Hdammthiol)(2)]Cl·3H(2)O [M = Cr(III) (1), Fe(III) (2)] [where H(2)dammthiol is the thiol form of the ligand, diacetylmonoxime morpholine N-thiohydrazone] were synthesized by metal template reactions of diacetylemonoxime with morpholine N-thiohydrazide in the presence of CrCl(3)·6H(2)O and FeCl(3)·6H(2)O. Both the complexes (1 and 2) were characterized by single crystal X-ray crystallography, spectroscopic (IR and UV-vis), Mössbauer and TGA analyses. The single crystal X-ray studies of both complexes show that the supramolecular hosts, constructed by the discrete mononuclear complexes, form supramolecular channels along the c-axis which are filled up by water-chloride clusters. In both complexes, the 1D water-chloride chain with chair-like architecture within the supramolecular hosts presents novelty. The magnetic measurement study of Fe(III) complex shows a spin crossover from S = 1/2 at 2.5 K to S = 5/2 at 300 K. At very low temperature, the presence of strong cooperative hydrogen bonding interactions stabilizes the S = 1/2 state.

Metal-promoted synthesis and characterization of Pr(III), Nd(III) and Eu(III) Schiff base complexes derived from salicylaldehyde and 4,9-dioxa-1,12- diaminododecane

The one-step metal template reaction of salicylaldehyde with 4,9-dioxa-1,12-diaminododecane in the presence of praseodymium(III), neodymium(III) or europium(III) nitrates gives complexes containing N,N’- bis(salicylidene)-1,12-diamino-4.9-dioxadodecane ligand with N2O4 set of donor atoms as a result of the [2+1] Schiff base condensation. The template reaction products were characterized by spectroscopic (IR, UV-Vis, ESI-MS) and analytical (elemental and thermogravimetric analysis) methods. All data indicate 1:1 ligand to metal stoichiometry.

An Unusual Nickel−Copper-Mediated Alkyne Homocoupling Reaction for the Active-Template Synthesis of [2]Rotaxanes

We report on an unusual Ni-/Cu-mediated alkyne homocoupling reaction, directed through the cavity of a bidentate macrocyclic ligand by chelated metal ions to furnish [2]rotaxanes in excellent (up to 95%) yields. This is the first active metal template reaction to employ an octahedral coordination geometry metal ion, Ni(II), and the study provides some interesting mechanistic insights into the mixed bimetallic reaction mechanism. The mixed-metal catalyst system was discovered serendipitously when Cu(I) was added to a Ni(II)-catalyzed alkyne homocoupling reaction in an attempt to facilitate chloride-acetylide ligand exchange. The role of Cu(I) in the reaction is, in fact, quite different from that originally intended. The effectiveness of having both nickel and copper present can be rationalized by the nature of a pi-activated, sigma-bonded, bimetallic intermediate in which the substitution of Ni(II) for one Cu(I) ion in the classic bimetallic Glaser reaction mechanism apparently aids reductive elimination of the acetylide ligands. The system may prove useful for the development of general mixed-metal protocols for catalytic alkyne coupling reactions as well as being a highly effective route to rotaxanes with bis-acetylene threads, which are potentially useful for materials applications (insulated molecular wires) and in molecular machines (rigid, nonfolding axles).

Synthesis, structure and spectroscopic properties of CuL(MeOH), H2L = (E)-N 1-(2-((2-aminocyclohexydiimino)(phenyl)methyl)-4-chlorophenyl)-N 2-(2-benzyl-4-chlorophenyl)oxalamide

A new kind of copper(II) complex, CuL(MeOH) (H2L = (E)-N 1-(2-((2-aminocyclohexydiimino)(phenyl)methyl)-4-chlorophenyl)-N 2-(2-benzyl-4-chlorophenyl)oxalamide) has been synthesized and its structure determined by single-crystal X-ray methods. Copper(II) ion is five-coordinate, bonding to four nitrogen atoms from H2L and one oxygen atom from MeOH. Hydrogen bonds in the crystal result in the formation of a one-dimensional structure. EPR spectra are discussed. Computer simulation gave g|| = 2.200, g⊥ = 2.002. On the basis of the synthesis and the crystal structure, the mechanism of the metal template reaction involved in the formation of the complex was verified.

Complexes with NSO and N2S2 Donor Ligands. Cobalt (II), Cobalt(III) and Nickel(II) Complexes Of 2,4-bis (2′-Mercapto-Phenylimino)Pentane, 2-(2-Mercaptophenyl)imino-4-pentanone and 2-(2-Mercaptophenyl)-salicylaldimine and Their Reactions

Abstract Reactions of acetylacetone and salicylaldehyde with 2-aminobenzenethiol yielded the benzothiazolines Hopatz and Hopbtz, respectively, rather than the corresponding Schiff bases. The reactions of benzothiazolines with Co(OAc)2.4H2O,Co(NO3)2.6H2O, Co(acac)2.2H2O and Ni(acac)2.H2O afforded the corresponding metal Schiff base chelates. Under suitable metal template reaction conditions two moles of 2-aminobenzenethiol have been found to condense with one mole of acetylacetone (in the diketo form) leading to the synthesis of Co(II) and Co(III) complexes of a quadridentate N2S2 donor ligand. The reaction of [CoII (pdmpi)]H2O {H2pdmpi = 2,4-bis (2′-tnercaptophenylimino) pentane} synthesized in this study, with Cd(NO3)2.4H2O and Mn(CO)5Br afforded [{coII(pdmpi)}2 Cd](NO3)2and [CoII (pdmpi) Mn(CO) 3Br] where CoII (pdmpi) functions as a bldentate S,S-donor metallo-ligand. The cobalt(II) complex CoII (pdmpi)H2O smoothly reacts with bifunctional alkylating agents like 1,2-dibromoethane to form the inacrocycli...

The influence of cavity size on the properties of encapsulated rhodium(III) lons: long-lived metal-centred emission in a symmetric expanded cavity rhodium cage system

Efficient and rapid metal template reactions of rhodium(III) hexaamine complexes with paraformaldehyde and nitromethane under non-aqueous conditions lead to both optimal and expanded cavity cage complexes with widely differing X-ray structures and electronic properties; the larger cavity homologues feature a strongly enhanced metal-centred phosphorescence in water at 77 K.

Preparation and characterization of nickel(II), copper(II) and palladium(II) complexes with 5,14‐dihydro‐7,16‐diethyl‐dipyrazo[b,i][1,4,8,11]tetraazacyclotetradecine

AbstractA novel macrocycle, 5,14‐dihydro‐7,16‐diethyldipyrazo[b,i][1,4,8,11]tetraazacyclotetradecine, has been synthesized from 1,2‐diaminopyrazine and 2‐ethyl‐3‐ethoxyacrolein. The absorption bands appearing in the energy range greater than 20000 cm−1 were attributable to the π → π transitions. The bands in the range of the 20100–23300 cm−1 show more bathochromic shift and greater intensity than those observed for corresponding 5,14‐dihydro‐7,16‐diethyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecine and/or 5,14‐dihydro‐7,16‐diethyl‐(Z)‐dipyrido[b,i][1,4,8,11]tetraazacyclotetradecine. The nickel(II), copper(II) and palladium(II) complexes of 5,14‐dihydro‐7,16‐diethyldipyrazo[b,i][1,4,8,11]tetraazacyclotetradecine have been synthesized using a metal template reaction. In 1H and 13C nmr spectra, the signals of annulene skeleton for metal‐free ligand and its complexes were found to observe in the lower field than those of the dibenzoanalogue.

Metal Template Reactions. XXIV. Synthesis of Macrocyclic Amide and Ester Complexes Via Substituted 1,1'-Oxalylbisisatins and the Deesterification of Some Ester Complexes

The 5-substituted phenylglyoxylic esters (3) and amides (4) have been prepared via the corresponding 1,1′-oxalylbisisatins (2). The nickel(11) macrocyclic amide complexes (7) have been prepared but the related ester complexes (5) were found to undergo deesterification (hydrolysis and decarboxylation) to provide a convenient route to the proto-complexes (6).

ChemInform Abstract: METAL TEMPLATE REACTIONS. XX. MACROCYCLIC METAL COMPLEXES DERIVED FROM 4,6-DIMETHOXY-3-METHYLINDOLE-2,7-DICARBALDEHYDE AND SOME PRIMARY DIAMINES WITH ADDITIONAL NITROGEN DONOR ATOMS

Chemischer InformationsdienstVolume 15, Issue 18 Organoelement Compounds ChemInform Abstract: METAL TEMPLATE REACTIONS. XX. MACROCYCLIC METAL COMPLEXES DERIVED FROM 4,6-DIMETHOXY-3-METHYLINDOLE-2,7-DICARBALDEHYDE AND SOME PRIMARY DIAMINES WITH ADDITIONAL NITROGEN DONOR ATOMS D. ST. C. BLACK, D. ST. C. BLACKSearch for more papers by this authorN. E. ROTHNIE, N. E. ROTHNIESearch for more papers by this authorL. C. H. WONG, L. C. H. WONGSearch for more papers by this author D. ST. C. BLACK, D. ST. C. BLACKSearch for more papers by this authorN. E. ROTHNIE, N. E. ROTHNIESearch for more papers by this authorL. C. H. WONG, L. C. H. WONGSearch for more papers by this author First published: May 1, 1984 https://doi.org/10.1002/chin.198418309Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume15, Issue18May 1, 1984 RelatedInformation

Metal template reactions. XX. Macrocyclic metal complexes derived from 4,6-Dimethoxy-3-methylindole-2,7-dicarbaldehyde and some primary diamines with additional nitrogen donor atoms

4,6-Dimethoxy-3-methylindole-2,7-dicarbaldehyde (6) has been prepared by the formylation of 4,6-dimethoxy-3-methylindole (5)itself prepared by the hydride reduction of the oxoindole (4). Macrocyclic nickel(II) and copper(II) complexes (8), (10) and (12) have been prepared from the dialdehyde (6), the appropriate metal(II) acetate and the primary diamines 2,2'-iminobisaniline (7), 2-amino-N-(2'-aminophenyl)benzamide (9) and 2-amino-N-(2'-aminobenzoyl)benzamide (11) respectively.

Metal template reactions. XVI. Design and synthesis of primary diamine ligands with additional nitrogen donor atoms

Five new primary diamines (8), (10), (12), (20) and (22) have been synthesized. These compounds contain additional nitrogen donor atoms suitable for metal chelation. An improved preparation of the triamine (6) is also reported.

Metal template reactions. XVIII. Macrocyclic metal complexes derived from 2,6-diacetylpyridine and some primary diamines with additional nitrogen donor atoms

Macrocyclic nickel(II), copper(II) and cobalt(II) complexes (6), (8), (10), (12) and (14) have been prepared from 2,6-diacetylpyridine, the appropriate metal salt and the primary diamines 2,2'-(iminodimethylene)bisaniline (5), azobenzene-2,2'-diamine (7), 2,2'-iminobisaniline (9), 2-amino- N-(2'-aminopheny1)benzamide (11) and 2-amino-N-(2'-aminobenzoy1)benzamide (13) respectively. The primary diamines 2,2'-diaminooxanilide (15) and N,N'-(2'-phenylene)bis(2'-aminobenzamide) (16) could not be incorporated into macrocyclic ligands by similar techniques.

Metal template reactions. XVII. The attempted dimerization of amino carbonyl compounds containing a supporting donor atom

Attempts to effect metal template condensative dimerizations of the amino aldehydes (4), (11) and(12) and the amino ketone (24) have been unsuccessful. Oxidation of the alcohol(9) did not allow isolation of the aldehyde (4). The alcohol (17) underwent oxidation to give crude aldehyde (11),but the latter gave an unidentified mixture of products on attempted reaction with metal ions. The alcohol (20) was stable to oxidation, probably because of hydrogen bonding. The amino aldehyde(12) could not be isolated from the reduction of the nitro aldehyde (22), the product being the alcohol(20). The amino ketone (24) was fully characterized, but proved unreactive in attempted reactions with metal ions, again possibly as a result of strong hydrogen bonding.

Metal template synthesis of chromium(III) complexes

Chromium(III) complexes of Schiff bases resulting from the condensation of one mole of diacetyl with two moles of ethylene-diamine or 1,3 diaminopropane has been isolated by metal template reaction. The isolated complexes have been assigned cis configurations.

Metal template reactions. XXI. Synthesis and coordination chemistry of diamino dialdehydes based on pyrimidines and related enaminones

4,6-Dichloropyrimidine-5-carbaldehyde (1) has been converted into the diamino dialdehydes (2)-(5). The related compound (6) could not be obtained but the pyrimido-diazepine (7) was formed instead. Copper(II) and nickel(II) complexes (8) were formed from the compounds (4) and (5). Forcing conditions were required for the formation of the macrocyclic complexes (9)-(12) from the precursors (4) and (5). The chloropyrimidines (2) and (3) underwent alkaline hydrolysis to give the enaminones (16) and (17) respectively. These compounds in turn gave rise to the complexes (21)-(23). Vigorous conditions were required for the formation of the macrocyclic complex (23) and the complex (22) was obtained by an amine exchange process.

Metal template reactions. XIX. Macrocyclic metal complexes derived from 2,2'-iminobisbenzaldehyde and some primary diamines with additional nitrogen donor atoms

Macrocyclic nickel(II), copper(II) and cobalt(II) complexes (6), (7), (9), (11), (13), (17) and (19) have been prepared from 2,2'-iminobisbenzaldehyde, the appropriate metal salt and the primary diamines 3,3'-iminobispropylamine (4), 2,2'iminobisethylamine (9, 2,2'-(iminodimethylene)bisaniline (8), azobenzene-2,2'-diamine (10), 2,2'-iminobisaniline (12), 2-amino-N-(2'-aminophenyl)benzamide (16) and 2-amino-N-(2'-aminobenzoyl)benzamide (18) respectively. The nickel(II) complex (15), zinc(11) complex (21) and copper(II) complex (22) were also prepared by similar methods. 2,2'-(Benzene- 1,2-diyldiimino)bisbenzaldehyde (25) was prepared but did not undergo metal template reactions to allow the formation of macrocyclic complexes.