16722-50-2Relevant academic research and scientific papers
Development of Photoactivatable Nitroxyl (HNO) Donors Incorporating the (3-Hydroxy-2-naphthalenyl)methyl Phototrigger
Zhou, Yang,Cink, Ruth B.,Fejedelem, Zachary A.,Cather Simpson,Seed, Alexander J.,Sampson, Paul,Brasch, Nicola E.
, p. 1745 - 1755 (2018/04/17)
A new family of photoactivatable HNO donors of general structure RSO2NHO-PT [where PT represents the (3-hydroxy-2-naphthalenyl)methyl (3,2-HMN) phototrigger] has been developed, which rapidly releases HNO. Photogeneration of HNO was demonstrated using the vitamin B12 derivative aquacobalamin as a trapping agent. The amount of sulfonate RSO2– produced was essentially the same as the amount of HNO released upon photolysis, providing a convenient method to indirectly quantify HNO release. Two competing pathways were also observed; a pathway involving O–N bond cleavage leading to release of a sulfonamide, and a pathway resulting in release of the parent Nhydroxysulfonamide RSO2NHOH (for HNO donors with Me- and Ph-containing leaving groups only). Up to approximately 70 % of the HNO-generating pathway was observed with the CF3-containing leaving group, with HNO generation favored for small percentages of aqueous buffer in the acetonitrile/pH 7.00 phosphate buffer solvent mixture. Characterization of the photoproducts obtained from steady-state irradiation by NMR spectroscopy showed that the desired HNO-generating pathway was less favored for HNO donors with Me- and Ph-containing leaving groups compared to the CF3-containing leaving group, suggesting that the excellent CF3-containing leaving group promotes HNO generation.
Nucleophilicity and nucleofugality of phenylsulfinate (PhSO 2-): A key to understanding its ambident reactivity
Baidya, Mahiuddin,Kobayashi, Shinjiro,Mayr, Herbert
supporting information; experimental part, p. 4796 - 4805 (2010/06/17)
Second-order rate constants for the reactions of the phenylsulfinate ion PhSO2- with benzhydrylium ions Ar2CH + have been determined in DMSO, acetonitrile, and aqueous acetonitrile solution using laser-flash and stopped-flow techniques. The rate constants follow the correlation equation log k (20 °C) = s(N + E), which allows the determination of the nucleophile-specific parameters N and s for PhSO2- in different solvents. With N = 19.60, PhSO 2- is a slightly weaker nucleophile than malonate and azide ions in DMSO. While PhSO2- reacts with highly stabilized benzhydrylium ions to give benzhydryl phenyl sulfones exclusively, highly reactive benzhydrylium ions give mixtures of sulfones Ar 2CH-SO2Ph and sulfinates Ar2CH-OS(O)Ph; the latter rearrange to the thermodynamically more stable sulfones through an ionization recombination sequence. Sulfones generated from PhSO2 - and stabilized amino-substituted benzhydrylium ions undergo heterolysis in aqueous acetonitrile and the rate of formation of the colored benzhydrylium ions was followed spectrophotometrically by stopped-flow techniques. The ranking of the electrofugalities of the benzhydrylium ions (i.e., the relative ionization rates of Ar2CH-SO2Ph) was not the inverse of the ranking of their electrophilicities (i.e., the relative reactivities of Ar2CH+ with nucleophiles), which was explained by differences in Marcus intrinsic barriers. While sulfones are thermodynamically more stable than the isomeric sulfinates, the intrinsic barriers for the attack of benzhydrylium ions at the oxygen of PhSO 2- are significantly lower than the intrinsic barriers for S-attack, and the activation energies for the attack of carbocations at sulfur are only slightly smaller than those for attack at oxygen. Because reactions of PhSO2- with carbocations of an electrophilicity E > -2 (i.e., carbocations which are more reactive than Ph3C+) are diffusion-controlled, the regioselectivities of the reactions of PhSO 2- with ordinary carbocations do not reflect relative activation energies.
Photochemical cleavage reactions of 8-quinolinyl sulfonates in aqueous solution
Kageyama, Yoshiyuki,Ohshima, Ryosuke,Sakurama, Kazusa,Fujiwara, Yoshihisa,Tanimoto, Yoshifumi,Yamada, Yasuyuki,Aoki, Shin
experimental part, p. 1257 - 1266 (2010/05/02)
Photochemical cleavage reactions of 8-quinolinyl benzenesulfonate derivatives and related sulfonates in aqueous solutions are reported. The 8-quinolinyl benzenesulfonates undergo photolysis upon photoirradiation at 300-330 nm to give the corresponding 8-quinolinols and benzenesulfonic acids with the production of only negligible amounts of byproducts. The effects of substituent groups of the 8-quinolinyl moiety and the benzene ring on the photolysis reactions were examined. Based on steady-state mechanistic studies using a triplet sensitizer, a triplet quencher, and electron donors, it was suggested that the photolysis proceeds mainly via the homolytic cleavage of S-O bonds in the excited triplet state.
Evidences for the generation of α-alkoxy and α-alkylthioalkyl radicals upon reduction of α-functionalized alkyl phenyl sulfones. Investigation of the reduction mechanism by electrochemistry
Amatore, C.,Bayachou, M.,Bontejengout, F.,Verpeaux, J. N.
, p. 371 - 381 (2007/10/02)
The mechanism of single electron transfer reduction of α-halo-, α-alkoxy-, or α-alkylthioalkyl phenyl sulfones is investigated using cyclic or steady-state voltammetry.This study provides strong evidence that some of these sulfones can be used to generate free radicals at potentials at which they cannot be reduced.Further confirmation is obtained by indirect electrolysis.Finally, redox catalysis allows determination of standard potentials and cleavage rate constants for most of the sulfone radical anions.Keywords: sulfones / single electron transfer / electrochemical reduction / alkoxyalkyl radicals / alkylthioalkyl radicals
Cathodic cleavage of heteroarylalkylsulfones: A facile route to long chain aliphatic sulfinates and relevant sulfones
Delaunay,Mabon,Chaquiq El Badre,Orliac,Simonet
, p. 2149 - 2150 (2007/10/02)
Heteroarylalkylsulfones - mainly pyridylalkylsulfones - exhibit a cathodic cleavage reaction producing alkanesulfinate anion in high yield. This reaction is tested with long chain alkyl groups and allows an easy synthesis of aliphatic sulfinic acids.
Se-Phenyl Areneselenosulfonates: Their Facile Formation and Striking Chemistry
Gancarz, Roman A.,Kice, John L.
, p. 4899 - 4906 (2007/10/02)
Benzeneseleninic acid reacts rapidly at 0 deg C with aromatic sulfinic acids according to the stoichiometry of eq 3 to form Se-phenyl arenesulfonates, PhSeSO2Ar (2), in high yield.In contrast to thiosulfonates, PhSSO2Ar, areneselenosulfonates are extremely photosensitive and undergo quite rapid photodecomposition.The principal products of this photodecomposition are the sulfonic anhydride, ArSO2OSO2Ar, and diphenyl diselenide.In the presence of added alkenes the facile photodissociation of 2 can be used to initiate a free-radical chain reaction that results in the addition of 2 to the alkene to form β-phenylseleno sulfones in good yield.The β-phenylseleno sulfones can be converted to synthetically useful α,β-unsaturated sulfones by oxidation of the β-phenylseleno group to the corresponding selenoxide and subsequent elimination of PhSeOH.Photoaddition of 2 to 2,5-norbornadiene to 5-(phenylseleno)-exo-3-nortricyclyl aryl sulfone as the almost exclusive product, while photoaddition to 1,5-cyclooctadiene gives a mixture of approximately equal amounts of the 1,2-adduct, 5-(phenylseleno)-6-arenesulfonyl-1-cyclooctene, and the product of transannular addition, 6-(phenylseleno)-exo-2-arenesulfonyl-cis-bicyclooctane.Besides their extraordinary ease of photodissociation, compounds 2 also react extremely readily with nucleophiles: Nu- + PhSeSO2Ar -> PhSeNu + ArSO2-.Kinetic studies show that the reactivity of PhSeSO2Ar with cyanide ion in such a reaction is 70000 times larger than the reactivity of the corresponding thiosulfonate, PhSSO2Ar.
