52671-72-4Relevant academic research and scientific papers
Synthesis and characterization of [3,3]- and [3,4]-perinophane
Buncel, Erwin,Mailloux, Nabil L.,Brown,Kazmaier, Peter M.,Dust, Julian
, p. 3559 - 3562 (2001)
Synthesis of [3,3]- and [3,4]-perinophanes is described via a novel route which will permit the synthesis of both symmetrical and unsymmetrical perinophanes and related cyclophane structures.
Mechanism of 1,4,5,8-naphthalene tetracarboxylic acid dianhydride hydrolysis and formation in aqueous solution
Barros,Cuccovia,Farah,Masini,Chaimovich,Politi
, p. 71 - 82 (2007/10/03)
The study of highly conjugated, carbonyl-containing molecules such as 1,4,5,8-naphthalene tetracarboxylic dianhydride, III, is of interest since reactivity differences and transmission of electronic effects through the conjugated framework can be evidenced. The kinetics of hydrolysis of III in aqueous solution were determined from 5 M acid to pH 10. In basic solution hydrolysis of III yields, sequentially, 1,4,5,8-naphthalene diacid monoanhydride, II, and 1,4,5,8-naphthalene tetracarboxylic acid, I. The second order rate constant for alkaline hydrolysis is 200 fold higher for the first ring opening. The water-catalyzed hydrolysis of III yields a pH-dependent mixture of ionic forms of I and II. The rate constant for water-catalyzed hydrolysis of III is 25 fold higher than that for II. In concentrated acid the rates for reaching equilibrium (I, II and III) increase and III is the major product. The pKas of I (3.24, 5.13 and 6.25) and II (3.05, 5.90) were determined by potentiometric, fluorescence and UV spectroscopy titrations and by quantitative fit of the kinetic and equilibrium data. The apparent, pH-dependent, equilibrium constants, KEqII, for anhydride formation between I and II were obtained from the UV spectra. The quantitative fit of kinetic and equilibrium data are consistent with the assumption that anhydride formation only proceeds with the fully protonated species for both I and II and permitted the estimation of the equilibrium constants for anhydride formation, KEqII. The value of KEqII (I II) between pH 1 and 6 was ca. 5. Geometry optimization calculations in the gas phase of the reactions of III in alkaline, neutral and acid conditions, at the DFT level of theory, gave electronic distributions that were qualitatively consistent with the experimental results. The Royal Society of Chemistry 2006.
Modulating charge transfer through cyclic D,L-α-peptide self-assembly
Horne, W. Seth,Ashkenasy, Nurit,Ghadiri, M. Reza
, p. 1137 - 1144 (2007/10/03)
We describe a concise, solid support-based synthetic method for the preparation of cyclic D,L-α-peptides bearing 1,4,5,8- naphthalenetetracarboxylic acid diimide (NDI) side chains. Studies of the structural and photoluminescence properties of these molecules in solution show that the hydrogen bond-directed self-assembly of the cyclic D,L-α-peptide backbone promotes intermolecular NDI excimer formation. The efficiency of NDI charge transfer in the resulting supramolecular assemblies is shown to depend on the length of the linker between the NDI and the peptide backbone, the distal NDI substituent, and the number of NDIs incorporated in a given structure. The design rationale and synthetic strategies described here should provide a basic blueprint for a series of self-assembling cyclic D,L-α-peptide nanotubes with interesting optical and electronic properties.
