426-79-9Relevant articles and documents
Anion-regulated transient and persistent phosphorescence and size-dependent ultralong afterglow of organic ionic crystals
Chen, Guilin,Guo, Sidan,Feng, Hui,Qian, Zhaosheng
supporting information, p. 14535 - 14542 (2019/12/09)
It is a formidable challenge to achieve highly efficient organic afterglow and readily tunable transient and persistent phosphorescence of organic materials because of the lack of valid design principles. Herein, we report the regulation of the transient and persistent room-temperature phosphorescence of organic ionic crystals by the alteration of anions, and the unique size-dependent ultralong afterglow of tetraphenylphosphonium perchlorate (TPP ClO4) crystals under ambient conditions. Three organic ionic crystals show sharply distinct triplet emissions based on three heavy-atom free anions by proper construction of donor-acceptor patterns in the crystals. TPP ClO4 crystals exhibit ultrabright transient phosphorescence and ultralong afterglow, and the gradual enhancement of the afterglow with the crystal size directly proves the generation of ultralong afterglow from aggregates with strong intermolecular interactions in the crystals. These results greatly contribute to the general design principles of highly efficient transient and persistent phosphorescence and their regulations by rational design. Highly sensitive detection and imaging of perchlorate ions are achieved in a phosphorescence turn-on manner based on the bright room-temperature phosphorescence of TPP ClO4 crystals, and valuable anti-counterfeiting applications of the ultralong afterglow of TPP ClO4 crystals are also demonstrated in practical examples.
Photolysis of (Arylmethyl)triphenylphosphonium Salts. Substituent, Counterion, and Solvent Effects on Reaction Products
Imrie, C.,Modro, T. A.,Rohwer, E. R.,Wagener, C. C. P.
, p. 5643 - 5649 (2007/10/02)
Quaternary (arylmethyl)phosphonium salts of the general formula ArCH2-PR3(+)Y(-) (Ar = substituted phenyl or 1-naphthyl; R = phenyl, ferrocenyl, or butyl; Y(-) = BF4(-) or halide) have been photolyzed in acetonitrile or in methanol.Photolysis involved the cleavage of the P-CH2 bond and the products derived from both, the arylmethyl radical and the carbocation, were formed.The proportion of the radical- and carbocation-derived products was determined as a function of substituents in group Ar, of groups R, counterions Y(-), and the solvent.For the nonoxidizable counterion (BF4(-), the proposed mechanism of the reaction involves initial homolysis, followed by the escape of the radical products from a solvent cage, or by the electron transfer from carbon to phosphorus, yielding the corresponding arylmethyl carbocation.The latter can either react with the solvent to form the observed carbocation-derived product or can undergo recombination with the tertiary phosphine formed to yield the starting phosphonium ion.Some indication of the "inverted substituent effect" resulting from the inhibition of single electron transfer from an easily oxidized radical was obtained.For the oxidizable counterions (halides), an additional pathway is suggested, that involves electron transfer from the anion, yielding the arylmethyl radical and the phosphine, thus decreasing the ionic/radical products ratio.
Neutral Square Planar Cobalt(III) Complexes
Brewer, John C.,Collins, Terrence J.,Smith, Milton R.,Santarsiero, Bernard D.
, p. 423 - 428 (2007/10/02)
The monoanionic square planar cobalt(III) complex, 4-HMPA-DMP)> (4) (H4HMPA-DMP = 2,4-bis(2-hydroxy-2-methylpropanamido)-2,4-dimethyl-3-oxopentane), has been prepared and characterized by 1H NMR, solid state and solution magnetic properties, X-ray crystallography, and IR spectroscopy.Compound 4, and related anionic square planar cobalt(III) complexes, can be alkylated at an amido-N oxygen atom to afford the first examples of neutral square planar cobalt(III) complexes.These species have been characterized by 1H NMR, solid-state magnetic properties, mass spectroscopy and elemental analysis, a solution molecular weight determination, and IR spectroscopy.All of the compounds exhibit well-resolved paramagnetically shifted 1H NMR spectra.Depending upon the donor properties, certain PAC ligands afford stable octahedral cobalt(III) complexes whereas others produce the coordinatively unsaturated square planar complexes.This is of potential significance in the search for new inorganic reagents for atom-transfer and inner-sphere oxidations.
