Synthesis, characterization and cation-induced dimerization of new aza-crown ether-appended metalloporphyrins

Abstract

New metalloporphyrins bearing one or two aryl-aza-crown ether moieties at meso-positions have been synthesized using a palladium catalyzed amination reaction and fully characterized by spectral techniques. X-Ray structural data have been presented for the zinc and copper complexes of mono-substituted aza-crown ether appended metalloporphyrins. UV-Vis and (1)H NMR spectroscopic studies showed that addition of K(+) cations to a solution of monomeric aza-crowned porphyrins in CHCl(3)/MeOH led to cation-induced dimerization of these porphyrins, whereas addition of Na(+) cations yielded a monomeric complex. Axial coordination of the exobidentate ligand (DABCO) to zinc complexes of aza-crowned porphyrins and following binding metal ions led to formation of sandwich complexes with high stability constants.

Synthesis of New Porphyrin Trimers via Buchwald-Hartwig Amination Reaction

“…The choice of catalyst and conditions was based on the results of our previous work of amination of bromophenylporphyrins with various amines. [24,25,33,34] The reaction between 5,15-bis(4-aminophenyl)porphyrin ZnPMes 2 (PhNH 2 ) 2 and 2 equivalents of 5-(4-bromophenyl)porphyrin ZnPPhBr has led to arylation of both amino groups yielding 21 % of porphyrin trimer ZnPMes 2 (PhNH) 2 -(ZnPPh) 2 ( Figure 2).…”

Transition Metal Catalysis in Porphyrin Modifications

“…[45] It was found that coordination of these ligands with sodium cation provided complexes of 10*Na(I) and 18*2Na(I) compositions, while a bigger potassium cation formed complexes of 2(10)*K(I) and 2(18)*2K(I) compositions, respectively.…”

“…DavePhos (L2) and BINAP (L4) were compared in the reactions with ethane-1,2-diamine and its N-methyl derivatives, piperazine, diaza-18-crown-6 ether and N,N',N"-triBOCcyclen (Scheme 2). [44,45] The reactions were carried out using 1.5 equiv. of macrocyclic polyamines and 5 equiv.…”

Syntheses, Structures and Photosensitizing Properties of New Pt(II) and Pd(II) Porphyrinates

“…The product was precipitated from CH 2 Cl 2 (4 ml) with hexane (2 ml) yielding 39.5 mg (80 %) of compound 2 as orange solid. (3). Coproporphyrin II tetraethyl ester (40 mg, 52.2 µmol) was dissolved in benzonitrile (5 ml) and Pt(PhCN) 2 Cl 2 (73.7 mg, 156.6 µmol) was added.…”

“…Many achievements of supramolecular chemistry such as preparing new materials are associated with porphyrin molecules linked by intermolecular non-covalent bonds. [1][2][3] Porphyrins and chlorins have applications as versatile sensors for bioassay, [4,5] active entities in pharmacological drugs for diagnostics and therapy of oncologic diseases. [6] The fundamental investigations in searching new analytical sensors are carried out widely in the world.…”