1128-52-5Relevant articles and documents
Electron acceptors of the fluorene series. 9. Derivatives of 9-(1,2- dithiol-3-ylidene)-, 9-(1,3-dithiol-2-ylidene)-, and 9-(1,3-selenathiol-2- ylidene)fluorenes: Synthesis, intramolecular charge transfer, and redox properties
Mysyk, Dmitrii D.,Perepichka, Igor F.,Perepichka, Dmitrii F.,Bryce, Martin R.,Popov, Anatolii F.,Goldenberg, Leonid M.,Moore, Adrian J.
, p. 6937 - 6950 (1999)
The synthesis and physical properties of four series of novel fluorene push-pull compounds (4-7) of the D-π-A type with intramolecular charge transfer (from 1,3- and 1,2-dithiole and 1,3-selenathiole donor (D) moieties) are described. The nature of the heteroatom (S or Se) in the donor fragment has no effect on the maxima of intramolecular absorption bands (λ(ICT)), whereas a change of position of the heteroatoms in the dithiole moiety from 1,3 to 1,2 leads to a substantial bathochromic shift in λ(ICT). Solvatochromism, thermochromism, and negative halochromism in these compounds are demonstrated. Cyclic voltammograms of 4-7 exhibit two, separate, single- electron reversible redox waves, the potentials of which (as well as the ICT energies in the molecules) are quantitatively described by σ(p)- constants of the substituents in the fluorene ring. Compounds 4-7 exhibit reversible salt formation in sulfuric acid, and for compound 5g in diluted sulfuric acid an additional absorption in the near-IR region has been observed that we attribute to radical species formation from the equilibrium [5g-H]+ + 5g ? 5g·+ + [Sg-H]·.
UNSATURATED THIOLATES AND THEIR ANALOGS IN CYCLOADDITION REACTIONS. XIII. REACTIONS OF POTASSIUM 2-ARYL- AND 2-ALKYLETHYNESELENOLATES WITH HETEROCUMULENES
Laishev, V. Z.,Petrov, M. L.,Petrov, A. A.
, p. 450 - 454 (2007/10/02)
Potassium 2-aryl- and 2-alkylethyneselenolates, obtained by the decomposition of 4-substituted 1,2,3-selenadiazoles, enter into a cyclization reaction with phenyl isothiocyanate to form isomeric N-(5-R-1,3-thiaselenol-2-ylidene)phenylamines.Measurement of the relative rate constants for cyclization of 2-(p-R-aryl)ethyneselenolates at the thione bond shows that the reaction is accelerated by donating substituents and retarded by withdrawing substituents.