A Triangle−Square Equilibrium of Metallosupramolecular Assemblies Based on Pd(II) and Pt(II) Corners and Diazadibenzoperylene Bridging Ligands
作者:Armin Sautter、Dietmar G. Schmid、Günther Jung、Frank Würthner
DOI:10.1021/ja004360y
日期:2001.6.1
which resulted in complex dynamic equilibria between molecular triangles 3a-d and molecular squares 4a-d in solution. Characterization of the equilibria and assignment of the metallacycles was accomplished by (1)H and (31)P[(1)H] NMR spectroscopy in combination with electrospray ionization Fourier transform ion cyclotron mass spectrometry (ESI-FTICR-MS). It was found that the equilibria depend on several
Synthesis of Diazadibenzoperylenes and Characterization of Their Structural, Optical, Redox, and Coordination Properties
作者:Frank Würthner、Armin Sautter、Joachim Schilling
DOI:10.1021/jo011133l
日期:2002.5.1
Tetraphenoxy-substituted diazadibenzoperylenes 5a,b were synthesized from tetrachloroperylene tetracarboxylic acid bisanhydride I through imidization with benzylamine, nucleophilic displacement of the four chlorine atoms by phenolates, carbonyl group reduction by LiAlH4/AlCl3, and subsequent Pd/C-promoted debenzylation-dehydrogenation. The structural properties of these extended diazaarenes are discussed on the basis of a X-ray crystal structure of the N,N'-dibutylated diazadibenzoperylenium dication 6, which revealed a 25degrees twist of the central six-membered ring leading to an atropisomeric pi-conjugated backbone. The chromophoric systems of 5 and 6 were characterized by optical absorption and fluorescence spectroscopy, which revealed an intense fluorescence with a quantum yield of 75% for 5 and 50% for 6. Cyclic voltammetry showed reversible oxidation and reduction waves for 6, whereas the oxidation of 5 afforded the irreversible deposition of a conductive film on the electrode surface. Finally, the potential use of ligands 5 in supramolecular chemistry has been evaluated by complexation experiments with carboxylic acids and zinc tetraphenylporphyrin (ZnTPP).
Substituted Diazadibenzoperylenes: New Functional Building Blocks for Supramolecular Chemistry