Poly(pyrazolyl)borates and related scorpionate ligands are some of the most widely studied ligands in chemistry. Their coordination chemistry has been extensively developed with particular interest arising out of the versatility of this class of ligands such as the ease of modifying the steric and electronic environment about the metal center by variation of the azolyl moiety or the substituents on the azolyl groups. The success and versatility of poly(pyrazolyl)borates has inspired the development of Scorpionate ligands that are based on other donor systems. In this field, we have explored the chemistry of functionalized Scorpionates by using carboxylic acid, ester-, amide-, trifluoromethyl- or nitro- containing groups on the azole rings to provide an additional set of sites able to interact with metals. Recently new nitroimidazole and glucosamine conjugated heteroscorpionate ligands, namely LMN and LDAC, respectively, were synthesized by direct coupling of preformed side chain acid and amine components. The related copper(II) complexes, {[(LMN)2Cu]Cl2} and {[(LDAC)2Cu]Cl2}, have been prepared and were evaluated for their cytotoxic activity towards a panel of several human tumour cell lines. We have also syntesized mono-, bis- and tris-(3-nitro-pyrazol-1-yl)borate ligands, and by reaction with CuX (X = (CH3CN)4PF6, Cl or I) in the presence of phosphines or isocyanides they afforded the corresponding Scorpionates supported copper(I) adducts; now we are completing this systematic study synthesizing the analogous silver(I) complexes. We have also designed the novel tris-(3-nitro-triazol-1-yl)borate ligand by reaction of 3-nitro-1,2,4-triazole with NaBH4 and the related copper(I) and silver(I) phosphine or isocyanide complexes.
Metal systems supported by Scorpionates
TRASATTI, Andrea;PELLEI, Maura;GIOIA LOBBIA, Giancarlo;MARINELLI, MARIKA;SQUARCIA, LORENZO;SANTINI, Carlo
2012-01-01
Abstract
Poly(pyrazolyl)borates and related scorpionate ligands are some of the most widely studied ligands in chemistry. Their coordination chemistry has been extensively developed with particular interest arising out of the versatility of this class of ligands such as the ease of modifying the steric and electronic environment about the metal center by variation of the azolyl moiety or the substituents on the azolyl groups. The success and versatility of poly(pyrazolyl)borates has inspired the development of Scorpionate ligands that are based on other donor systems. In this field, we have explored the chemistry of functionalized Scorpionates by using carboxylic acid, ester-, amide-, trifluoromethyl- or nitro- containing groups on the azole rings to provide an additional set of sites able to interact with metals. Recently new nitroimidazole and glucosamine conjugated heteroscorpionate ligands, namely LMN and LDAC, respectively, were synthesized by direct coupling of preformed side chain acid and amine components. The related copper(II) complexes, {[(LMN)2Cu]Cl2} and {[(LDAC)2Cu]Cl2}, have been prepared and were evaluated for their cytotoxic activity towards a panel of several human tumour cell lines. We have also syntesized mono-, bis- and tris-(3-nitro-pyrazol-1-yl)borate ligands, and by reaction with CuX (X = (CH3CN)4PF6, Cl or I) in the presence of phosphines or isocyanides they afforded the corresponding Scorpionates supported copper(I) adducts; now we are completing this systematic study synthesizing the analogous silver(I) complexes. We have also designed the novel tris-(3-nitro-triazol-1-yl)borate ligand by reaction of 3-nitro-1,2,4-triazole with NaBH4 and the related copper(I) and silver(I) phosphine or isocyanide complexes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
