Synthesis and characterization of new 13 and 14-membered macrocycles and their transition metal complexes

Two new macrocyclic ligands 1,4,7,9,12-pentaaza-10,11-dioxo-8,9,12,13-bis-(1-oxo-3-thio-2-hydropyrimidine)-trideca-7,13-diene, (L¹) and 1,4,7,9,12-pentaaza-10,12-dioxo-8,9,13,14-bis-(1-oxo-3-thio-2-hydropyrimidine)-tetradeca-7,14-diene, (L²) and their complexes with Cr^III, Mn^II, Fe^III, Co^II, Ni^II, Cu^II and Zn^II have been synthesized, and characterized by elemental analysis, i.r., ¹H-n.m.r., e.p.r., u.v.–vis. spectroscopy, magnetic susceptibility and conductance measurements. The conductivity measurements suggest that the complexes of divalent metal ions are 1:1 electrolytes whereas the trivalent metal ions are non-electrolytes. On the basis of electronic spectra and magnetic moment measurements the Cr^III and Fe^III complexes are octahedral, while the divalent metal complexes are tetrahedral except for the Ni^II and Cu^II complexes which are proposed to have square planar geometry. All the ligands and their complexes have been screened against gram-positive bacteria Staphylococcus aureus and gram-negative bacteria E. coli. The results show that they inhibit the growth of bacteria.     

Transition metal complexes of 13- and 14-membered N2O2 macrocycles: synthesis and characterization

Two novel series of 13- and 14-membered diazadioxamacrocyclic complexes [ML¹Cl₂] and [ML²Cl₂] (M=Co²⁺, Ni²⁺, Cu²⁺, and Zn²⁺) have been synthesized via the condensation reaction of o-aminophenol and 1,2-dibromoethane with a dialdehyde or a diketone in the presence of transition metal ions as templates in ethanol. The mode of bonding and overall geometry of the complexes have been inferred through IR, ¹H NMR, EPR, and electronic spectral studies, conductivity, and magnetic moment measurements. An octahedral geometry is proposed for all the complexes.     

New 14-membered octaazamacrocyclic complexes of divalent transition metal ions with their antimicrobial and spectral studies

A novel series of macrocyclic complexes of the type [M(C₁₈H₁₄N₁₀S₂)X₂]; where M = Co(II), Ni(II), Cu(II), Zn(II) and Cd(II); X = Cl^?, NO₃^?, CH₃COO^? has been synthesized by [2+2] condensation of thiocarbohydrazide and isatin in the presence of divalent metal salts in methanolic medium. The complexes have been characterized with the help of elemental analyses, conductance measurements, magnetic measurements, electronic, NMR and infrared spectral studies. The low value of molar conductance indicates them to be non-electrolytes. On the basis of various studies a distorted octahedral geometry may be proposed for all of these complexes. These metal complexes were also tested for their in vitro antimicrobial activities against some Gram-positive bacteria viz.Staphylococcus aureus, Bacillus subtilis, and some Gram-negative bacteria Escherichia coli, Pseudomonas aeruginosa and some fungal strains Aspergillus niger, Aspergillus flavus (molds), Candida albicans, Saccharomyces cerevisiae (yeasts). The results obtained were compared with standard antibiotic: Ciprofloxacin and the standard antifungal drug: Amphotericin-B.     

Synthesis,spectroscopic studies,and antibacterial activities of 14-membered tetraazamacrocyclic complexes of divalent transition metal ions

A new series of macrocyclic complexes, [M(C₄₈H₃₂N₄)X₂], where M?=?Co(II),?Ni(II),?Cu(II), and Zn(II); X?=?Cl^?,?NO₃ ^?,?CH₃COO^?, have been synthesized by condensation of 1,8-diaminonaphthalene and benzil, in the presence of divalent metal salts in methanolic medium. The complexes have been characterized by elemental analyses, conductance measurements, magnetic measurements, and electronic, NMR, IR, and MS spectral studies. The low value of molar conductance indicates the presence of non-electrolytes. A distorted octahedral geometry is proposed for the complexes. The metal complexes were also tested for their in vitro antibacterial activities against some bacterial strains and compared with the standard antibiotic Ciprofloxacin. Some tested complexes show good antibacterial activities against some bacterial strains.     

Novel porphyrinoid macrocycles and their metal complexes

The cornucopia of novel porhyrinoid macrocycles that - as a result of a symbiotic link between annulene and porphyrin chemistry - has emerged from the Cologne laboratory over the last decade is reviewed.     

Synthesis of first representatives of 46-membered P,N,O-containing cyclophanes and their transition metal complexes

Russian Chemical Bulletin - A condensation of phenyl- or l-menthylphosphine with formaldehyde and 4,4´-bis-(4´-aminophenoxy)biphenyl proceeding as a covalent self-assembly gave rise to...     

Macrocyclic metal complexes: synthesis and characterization of 14- and 16- membered tetraaza macrocyclic complexes of transition metals

A new 14-membered macrocyclic ligand, 5,7,12,14-dibenzo-2,3,9,10-tetraoxa-1,4,8,11-tetraazacyclotetradecane and a 16-membered ligand, 6,8,14,16-dibenzo-4,12-dimethyl-2,10-diphenyl-1,5,9,13-tetraazacyclohexadeca-1,5,9,12-tetra-ene and their transition metal complexes were prepared by the template method and characterized on the basis of elemental analysis, i.r., ¹H-n.m.r., electronic spectral studies, conductivity and magnetic susceptibility measurements.     

The preparation of a series of 12-, 13- and 14-membered tetra-imine macrocycles and characterization of their copper(II) complexes

Summary The 12-, 13- and 14-membered tetraphenyl substituted macrocycles Ph₄[12]TIM (2,3,8,9-tetraphenyl-1,4,7,10-tetra-azacyclododeca-1,3,7,9-tetraene), Ph₄[13]TIM (2,3,8,9-tetraphenyl-1,4,7,10-tetra-azacyclotrideca-1,3,7,9-tetraene) and Ph₄[14]TIM (2,3,9,10-tetraphenyl-1,4,8,11-tetradeca-1,3,8,10-tetraene) were prepared and their copper(II) complexes characterised. Magnetic and spectroscopic measurements (i.r. and u.v.-vis.) are discussed. A variety of macrocyclic precursers (KIM = 1,2,8,9-tetraphenyl-3, 7-diaza-2,7-dione) and KIM-dioxime were also prepared and characterised.     

Synthesis of new lariat cyclicdiamides and their metal complexes

Three new lariat dilactam host molecules were prepared by the reaction of triethyleneglycol dicarboxylic acid dichloride withN,N-disubstitutèd-4,7-dioxa-1,10-diazadecane precursors. The amide nitrogen pivot of such compounds are substituted with the benzyl, octyl and dodecyl groups. The complexing ability of these dilactams is displayed with a series of metal complexes of Na⁺, K⁺, Ca²⁺, Sr²⁺, Pb²⁺ and Ag⁺ ions. The structures determined are consistent with the data of¹H-NMR,¹³C-NMR, IR spectra and elemental analyses.Presented at the Sixth International Seminar on Inclusion Compounds, Istanbul, Turkey, 27–31 August, 1995.     

DFT analysis of molecular structure of 14-membered tetraaza-, dioxotetraaza-, and hexaazamacroheterocyclic ligands and their metal complexes

The structure of 14-membered macrocyclic chelants 1,4,8,11-tetraazacyclotetradecane-2,3,9,10-tetrathione, 1,3,6,8,10,13-hexaazacyclotetradecane-4,5,11,12-tetrathione, and 1,8-dioxa-3,6,10,13-tetraaza-cyclotetradecane- 4,5,11,12-tetrathione as well as their complexes with M(II) metals (M = Cr, Mn, Fe, Co, Ni, Cu, and Zn) has been simulated using OPBE/TZVP density functional method.     

The synthesis and characterization of ( E,E )-dioxime and its transition metal complexes containing 12-membered macrocycles linked to ferrocenyl-methyl groups

13,14-bis(Hydroxyimino)-4,7-bis(ferrocenylmethyl)-2,3,4,5,6,7,8,9-octahydrobenzo[k]-4, 7-diaza-1,10-dithiacyclododecine[13,14-g]-quinoxaline (H₂L) has been prepared from (E,E)-dichloroglyoxime and 12,13-diamino-4,7-bis(ferrocenylmethyl)-2,3,4,5,6,7,8,9-octahydrobenzo[k]-4,7-diaza-1,10-dithiacyclododecine which was synthesized from 12,13-dinitro-4,7-bis(ferrocenylmethyl)-2,3,4,5,6,7,8,9-octahydrobenzo[k]4,7-diaza-1,10-dithia cyclododecine. Mononuclear nickel(II) and copper(II) complexes of H₂L have a metal-ligand ratio of 1?:?2 and the ligand coordinates through two nitrogen atoms, as do most (E,E)-dioximes. The homotrinuclear [Cu(L)₂Cu₂(dipy)₂](NO₃)₂ compound coordinates to the other two copper(II) ions through deprotonated oximate oxygens and two 2,2′-dipyridyl as an end-cap ligand to yield the trinuclear structure. The ligand and its complexes have been characterized on the basis of ¹H, ¹³C NMR, IR and MS spectroscopy and elemental analyses.     

Metal ion-directed synthesis of 16-membered tetraazamacrocyclic complexes and their physico-chemical studies

Complexes of Co(II), Ni(II), Cu(II) and Zn(II) containing macrocyclic tetradentate nitrogen donor (N4) ligand have been synthesized from the template condensation reaction between o-phthalaldehyde and o-phenylenediamine. The newly synthesized ligand and its complexes have been characterized on the basis of results of elemental analysis, molar conductance, magnetic susceptibility measurements, FT-IR, electronic, 1H FT NMR spectral data and Job's method. Their thermal behaviour has been studied by the thermogravimetric analysis. An octahedral geometry has been proposed for all of these complexes except the copper complexes, which show distorted octahedral geometry. The low conductivity data suggest their non-ionic nature. The biological activities of the metal complexes have also been studied against different bacteria.     

Synthesis of new ligands for transition metal complexes: menthyl- and neomenthyl-cyclopentadienes

Syntheses of (?)-menthylcyclopentadiene (MCp) and (+)-neomenthyl cyclopentadiene (NMCp) from (?)-menthol are described. These chiral ligands have been used to prepare (η⁵-MCp)₂TiCl₂, (η⁵-NMCp)₂, TiCl₂, (η⁵-MCp)₂ZrCl₂, (η⁵-NMCp)₂ZrCl₂, (η⁵-Cp)(η⁵-MCp)TiCl₂ and (η⁵-Cp)(η⁵-NMCp)TiCl₂. The structure and absolute configuration of (η⁵-Cp)(η⁵-MCp)TiCl₂ has been established by X-ray analysis.     

Synthesis of new polyamidoximes and their crosslinking by transition metal ions

Three new polyamidoximes (PAO) having appropriate functionalities to bind transition metal ions were prepared. The polymers were obtained by the reaction of dichlorooximino ethane with the corresponding diamine. Characterization and crosslinking of PAOs via coordination with transition metal ions such as Ni(II), Co(II), Cu(II), and UO₂(II) are presented. The crosslinked polymer complexes exhibit good thermal stability. It was also found that both square planar and tetrahedral coordination structures are present in the crosslinked polymers.     

The synthesis and characterization of some new vic-dioximes and their transition metal complexes

In this study, three new vic-dioximes, [L¹H₂], N-(5-chloro-2-methoxyphenyl)amino-1-acetyl-1-yclohexenylglyoxime, [L²H₂],N-(3-chloro-4-methoxyphenyl)amino-1-acetyl-1-cyclohexenylgly-oxime and [L³H₂], N-(3-chloro-2-methoxyphenyl)amino-1-acetyl-1-cyclohexenylglyoxime were synthesized from 1-acetyl-1-cyclohexeneglyoxime and the corresponding substituted aromatic amines. Metal complexes of these ligands were also synthesized with Ni(II), Cu(II) and Co(II) salts. The structures of these new compounds (ligands and complexes) were characterized with FT-IR, magnetic susceptibility measurement, molar conductivity measurements, mass spectrophotometer measurements, thermal methods (TGA), ¹H NMR and ¹³C NMR spectral data and elemental analyses.     

Sulfur-functionalized N-heterocyclic carbenes and their transition metal complexes

Donor group functionalized N-heterocyclic carbenes (NHC) are an important class of ligands used in transition metal complex chemistry. Herein, the growing field of sulfur-functionalized NHC compounds and their respective transition metal complexes are described comprehensively. The sulfur-functionalized NHC compounds are categorized by functional groups such as thiolate, thioether, sulfoxide, thiophene, sulfonate and sulfonamide. Chiral compounds and the hemilabile behaviour of sulfur-functionalized NHC compounds are reported.     

New glyoxime derivatives and their transition metal complexes

Two new vic-dioxime ligands and their complexes with Co⁺², Ni⁺², Cu⁺², Cd⁺², and Zn⁺² ions were synthesized. Primer amines (3,4-methylenedioxaaniline and 4-methylbenzylamine) reacted with antichloroglyoxime to give 3,4-methylenedioxaphenylaminoglyoxime (H₂L¹) and N-(4-methylbenzyl)aminoglyoxime (H₂L²) ligands. Structures of the ligands and their complexes are proposed based on elemental analyses, IR, UV-Vis, and ¹H NMR spectra, magnetic susceptibility measurements, and thermogravimetric analyses (TGA). The article was submitted by the authors in English.     

Demonstration of 14-20-membered intramolecular carbonyl ylides: diastereoselective synthesis of macrocycles incorporating spiro-indolooxiranes

A range of macrocycles (13-19-membered) possessing spiro-indolooxirane unit were synthesized with complete diastereoselectivity in good yield by the rhodium(II) acetate catalyzed reaction of substituted cyclic diazoamides in dry dichloromethane. The reaction proceeds via the formation of the corresponding macrocyclic carbonyl ylide followed by a con-rotatory electrocyclization process.