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A method of direct borylation of vinyl-substituted porphyrinoids (porphyrins and chlorins) has been developed based on the copper catalyzed vinylic C–H activation.

“Roof shaped” chiral diamidophosphites of various structures and denticities were obtained and tested in Pd-catalyzed asymmetric allylic substitution.

Copper(I) halide and palladium(II) chloride complexes with tricyclic monastrol analogs containing the oxadiazocine ring have been synthesized and studied. The structures of the complexes were investigated with IR, NMR and UV spectroscopy. Two complexes, [Cu(L1)2Cl] and [Pd(L1)2Cl2], were structurally characterized by X-ray single-crystal and powder diffraction respectively. All the obtained coordination compounds were mononuclear. The ligands were coordinated with copper(I) and palladium(II) only via the soft sulfur atoms of thiocarbamide fragments, while the harder nitrogen and oxygen atoms remained uncoordinated. The palladium center was coordinated by two Cl ions and two S atoms from two 4-thioxo[1,3,5]oxadiazocine ligands in a distorted square-planar geometry. Copper(I) formed a trigonal planar geometry. The complexes demonstrated significant antibacterial activity towards the Escherichia coli K12 TG 1 bacterial strain in contrast to the free ligands, which didn’t show any noticeable activity.

Novel diamino and azamacrocycle functionalized porphyrins were efficiently synthesized by palladium-catalyzed amination of mono- and bis(meso-(bromophenyl))porphyrins. The optimization of reaction conditions allowed us to achieve high yields of products with substrates of different types. Supramolecular utility of the thus obtained aminoporphyrins was shown by investigations of processes of coordination self-assembly in solution by NMR and UV-Vis spectroscopy. The crystalline 1D-coordination polymer formed via self-assembly of N,N-dimethylethylenediamine substituted zinc porphyrin was characterized by X-ray diffraction.

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.

The reactions of tetrachloroauric(III) acid (HAuCl4) with the thioamides; 2-mercapto-benzothiazole (mbztH) and 5-ethoxy-2-mercapto-benzimidazole (EtmbzimH) lead to the desulfuration of the ligands and the formation of the ionic complexes {[AuCl4]- [bztH2]+} (1), and {[AuCl4]- [EtbzimH2]+ (H2O)} (2) (where bztH2+ and EtbzimH2+ are the desulfurated cations of the starting ligands). The reaction of HAuCl4 with 2-mercapto-nicotinic acid (mnaH2), however results in the formation of 2-sulfonate-nicotininc acid (C6H5NO5S) (3) with the simultaneous oxidation of the sulfur atom. On the other hand, the reactions of the gold(I) complex [Au(tpp)Cl] (4) (tpp = triphenylphosphine (Ph3P)) with the thioamides; 2-mercapto-thiazolidine (mtzdH), 2-mercapto-benzothiazole (mbztH) and 5-chloro-2-mercapto-benzothiazole (ClmbztH) in the presence of potassium hydroxide resulted in the formation of the gold(I) complexes of formulae [Au(tpp)(mtzd)] (5), [Au(tpp)(mbzt)] (6) and [Au(tpp)(Clmbzt)] (7) without ligand desulfuration. All complexes have been characterized by elemental analysis, FT-IR, far-FT-IR,1H-NMR, spectroscopic techniques and X-Ray crystallography. The electrochemical behavior of 1, 2 and 4-7 complexes and the ligands EtmbzimH, mbztH and mnaH2 was also studied in acetonitrile and DMF using cyclic voltammetry. The results are in support of a mechanism of desulfuration of the ligands by Au(III), involving a first oxidation of S to -SO3-, followed by a C-S bond cleavage. This is also supported by PM6 calculations of bond dissociation energies of the various compounds involved. Complexes 1, 2 and 4-7 were tested for in vitro cytotoxicity against leiomyosarcoma cells and the results are discussed in relation with the geometry of the complexes and compared with those of cisplatin and other metals. Complexes 1 and 5 showed higher activity than that of cisplatin, while HAuCl4 was inactive against sarcoma cells.