Chiral, π-conjugated 3,4-butano-1-phenyl-2,5-bis(2-pyridyl)phosphole derivatives 1a(2,2') and 1a(3) with chiral trans-1,2-diol moieties and fused pinene derivatives, respectively, were prepared from the corresponding chiral diynes by using the Fagan-Nugent method. Their UV/Vis absorption and chiroptical properties (optical rotation and circular dichroism) were studied. Their behavior as N,P,N chelates towards coordination of Cu(I) and formation of chiral supramolecular assemblies with π-conjugated ditopic dicyano ligands was investigated.
View Article and Find Full Text PDFAza[n]helicene phosphole derivatives have been prepared from aza[n]helicene diynes by the Fagan-Nugent route. Their photophysical properties (UV/Vis absorption and emission behavior) have been evaluated. Their behavior as P,N chelates towards coordination to Pd(II) and Cu(I) has been investigated: metal-bis(aza[n]helicene phosphole) assemblies are formed by a highly stereoselective coordination process, as demonstrated by X-ray crystallography.
View Article and Find Full Text PDFThe synthesis of phosphole-modified aza[6]helicenes and the complexation of these pi-conjugated ditopic ligands with metallic ions are described. The chiroptical properties of these metal-bis(helicene) assemblies were experimentally evaluated and studied by first-principles theoretical calculations. The results show that the metal impacts the chiroptical properties of these complexes through electronic interactions with the chiral pi-conjugated ligands.
View Article and Find Full Text PDFPhosphole-modified aza[4]helicenes act as heteroditopic chelates toward metal ions having different coordination geometries (Pd(II), Cu(I)).
View Article and Find Full Text PDFSelf-assembly of CuI dimers, featuring a bridging phosphole ligand, and ditopic cyano-substituted chromophores affords nanosize supramolecular cationic rectangles. Due to the short Cu-Cu distance in the bimetallic clips, the coordinated chromophores are forced to participate in cofacial pi-pi interactions as evidenced by X-ray data. In addition, intermolecular pi-pi interactions in the solid state are observed leading to infinite columns of pi-stacked (para-phenylenevinylene)-based chromophores.
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