77474-06-7Relevant articles and documents
Syntheses and magnetic properties of N-[2-(2-hydroxyethylthio)phenyl]arenesulfonamidatocopper(II) chelates
Emori, Shuji,Inoue, Motomichi,Kishita, Michihiko,Kubo, Masaji,Mizukami, Satoshi,Kono, Masao
, p. 2419 - 2422 (1968)
Various N-[2-(2-hydroxyethylthio)phenyl]arenesulfonamidatocopper(II) chelates and the addition compounds thereof with methanol or ethanol were synthesized, and several typical ones were subjected to magnetic determination at temperatures between about 80
Benzo-Fused 1,4-Heterocycles via Dialkyl Carbonate Chemistry
Musolino, Manuele,Aricò, Fabi
, p. 1770 - 1778 (2019/04/05)
A novel halogen-free synthesis of benzo-fused six-membered 1,4-heterocycles through the chemistry of dialkyl carbonates is reported. Commercially available catechol, 2-aminophenol, and 2-aminothiophenol were reacted first with ethylene carbonate in an autoclave to give O -hydroxyethyl, N -hydroxyethyl, and S -hydroxyethyl derivatives respectively, through a B Al 2 mechanism. Then 2-(2-hydroxyethoxy)phenol and 2-(2-hydroxyethylamino)phenol were cyclized in excellent yields by reaction with dimethyl carbonate (DMC) and DABCO as a bicyclic organic base to give the corresponding benzodioxine and benzoxazine derivative, respectively. Moreover, 2-(2-aminophenylthio)ethanol afforded the benzothiazine derivative in good yield by reaction with DMC with an excess of a strong base such as NaH. The investigation on the cyclization reaction has highlighted that several equilibria are involved leading to the formation of carbonate and carbamate intermediates through B Ac 2 mechanisms. Depending on the reaction conditions employed, these intermediates may undergo either kinetic-controlled ring closure by a B Al 2 mechanism or by-product formation.
Efficient reduction of nitroarenes over nickel-iron mixed oxide catalyst prepared from a nickel-iron hydrotalcite precursor
Shi, Qixun,Lu, Rongwen,Lu, Lianhai,Fu, Xinmei,Zhao, Defeng
, p. 1877 - 1881 (2008/09/17)
Nickel-iron mixed oxide prepared from a nickel-iron hydrotalcite precursor was found to be a highly efficient catalyst for the chemoselective reduction of nitroarenes under mild reaction conditions.
Formation of Benzoxathiete under Mild Conditions and Its Valence Tautomerism in Solution to Monothio-o-benzoquinone: An Experimental and Quantum Chemical Study
Naghipur, Ali,Reszka, Krzysztof,Sapse, Anne-Marie,Lown, J. William
, p. 258 - 268 (2007/10/02)
Aprotic diazotization of 2-aniline in dimethoxyethane affords products that include biphenylene and dibenzo-1,4-oxathiane.Detection of these products is consistent with the formation of benzoxathiete and the valence tautomerism to monothio-o-benzoquinone with concomitant formation of dehydrobenzene by a competing pathway.The latter was independently trapped with 1,3-diphenylisobenzofuran and with 9,10-dimethylanthracene.The requirement for SO group participation in the formation of benzoxathiete is established by comparison with the behavior of the analogous thioether and sulfone compounds.EPR and spin-trapping experiments confirm the intermediacy of both oxygen- and nitrogen-centered free radicals which is consistent with the homolytic pathways proposed for the diazotization process.Parallel aqueous diazotization of 2-aniline affords vinyl acetate, phenol, and halobenzene consistent with the generation of dehydrobenzene but not benzoxathiete under these conditions.Spin-trapping/EPR studies gave no evidence for free-radical components in the protic diazotization reaction.Ab initio calculations using the 3-21G* and 6-31G* basis sets within the Hartree-Fock approximation, as well as the MP2/3-21G* method, predict an energetically feasible tautomerism of benzoxathiete to monothio-o-benzoquinone.The 3-21G* calculations reveal the presence of a biradical intermediate for this reaction which, as a singlet, features an energy higher than the benzoxathiete by 33 kcal/mol, while as the corresponding triplet it proves to be lower in energy than the benzoxathiete by 2.5 kcal/mol.This process, however, might be symmetry forbidden.By contrast, the symmetry-allowed cycloreversion pathway of benzoxathiete to dehydrobenzene and SO is energetically much less favorable.
