25889-63-8Relevant articles and documents
Molecular clips with extended aromatic sidewalls as receptors for electron-acceptor molecules. Synthesis and NMR, photophysical, and electrochemical properties
Branchi, Barbara,Balzani, Vincenzo,Ceroni, Paola,Kuchenbrandt, Mireia Campana,Klaerner, Frank-Gerrit,Blaeser, Dieter,Boese, Roland
, p. 5839 - 5851 (2008)
(Figure Presented) We have synthesized molecular clips 1 comprising (i) two benzo[k]fluoranthene sidewalk and (ii) a dimethylene-connected benzene bridge that carries two acetoxy (1a), hydroxy (1b), or methoxy (1c) substituents in the para position. Their NMR spectra, single-crystal structures, and photophysical (fluorescence intensity, lifetime, depolarization) and electrochemical properties are discussed. For the purpose of comparison, similar compounds (2 and 3) containing only one benzo[k]fluoranthene unit have been prepared and studied. The strongly fluorescent clips 1 form stable complexes with electron-acceptor guests because of a highly negative electrostatic potential on the inner van der Waals surface of their cavity. The complexation constants in chloroform solution for a variety of guests, determined by NMR and fluorescence titration, are much larger than those of the corresponding anthracene and naphthalene clips (4 and 5), particularly in the case of extended aromatic guests. The effect of the substituents in the para position of the benzene spacer unit of clips 1 is discussed on the basis of the host-guest complex structures obtained by X-ray analysis and molecular mechanics simulations. In the case of 9-dicyanomethylene-2,4,7-trinitrofluorene (TNF) guest, complex formation with clip 1a causes dramatic changes in the photophysical and electrochemical properties: (i) a new charge-transfer band at 600 nm arises, (ii) a very efficient quenching of the strong benzo[k]fluoranthene fluorescence takes place, (iii) shifts of both the first oxidation (clip-centered) and reduction (TNF-centered) potentials are observed, and (iv) reversible disassembling of the complex can be obtained by electrochemical stimulation.
Synthesis of novel fluoranthene-based conformationally constrained α-amino acid derivatives and polycyclic aromatics via the diels-alder reaction
Kotha, Sambasivarao,Meshram, Milind
, p. 1525 - 1531 (2014/06/10)
Conformationally constrained cyclic α-amino acid moieties have been fused to the fluoranthene system. Aminoindanecarboxylic acid (Aic) and 1,2,3,4-tetrahydroisoquinolinecarboxylic acid (Tic) derivatives were synthesized by an alkylation sequence, whereas a aminotetralincarboxylic acid (Atc) derivative was assembled using the Diels-Alder reaction as a key step. These α-amino acid derivatives are considered as constrained analogues of phenylalanine (Phe) and play an important role in the design and synthesis of bioactive peptides and some fluorescence chemosensor molecules. Moreover, this strategy has been extended to polycyclic aromatics via the Diels-Alder reaction and subsequent aromatization with DDQ. Georg Thieme Verlag Stuttgart New York.
Benzannulation via ruthenium-catalyzed diol-diene [4+2] cycloaddition: One- and two-directional syntheses of fluoranthenes and acenes
Geary, Laina M.,Chen, Te-Yu,Montgomery, T. Patrick,Krische, Michael J.
, p. 5920 - 5922 (2014/05/20)
A new benzannulation protocol is described and applied to the synthesis of polycyclic aromatic hydrocarbons. Ruthenium(0)-catalyzed diol-diene [4+2] cycloaddition delivers cyclohex-1-ene-4,5-diols, which are subject to aromatization upon dehydration or Nicholas diol deoxydehydration. Employing diol and tetraol reactants, benzannulation can be conducted efficiently in one- and two-directional modes, respectively, as illustrated in the construction of substituted fluoranthenes and acenes.
