Fused-Ring Thiadiazines: Preparation and Crystallographic Characterization of 3-Phenyl Derivative of Benzo-, Pyridio[2,3-<i>e</i>]-, Pyrazino[2,3-<i>e</i>]-, and Tetrafluorobenzo-[1,2,4]thiadiazines
作者:Józef Zienkiewicz、Piotr Kaszynski、Victor G. Young
DOI:10.1021/jo035835h
日期:2004.4.1
favorable by about 2 kcal/mol than in the analogous sulfoxide. Crystal and molecularstructures of three out of the four thiadiazines were established by single-crystal X-ray analysis. All thiadiazines were found as the 4H tautomers with the heterocyclic ring puckered along the S(1)···N(4) line. The benzo derivative 1a forms a unidimensional N(4)−H···N(2) chain, the pyrazino derivative 1c forms dimeric
从相应的am 2分两步制备了四个双环4 H- [1,2,4]噻二嗪1a - d,产率为74-88%。通过从中间体S-丙基亚硫亚胺12中热消除丙烯获得了它们中的三个,即1a,1b和1d。吡嗪衍生物1c是由2c得到的亚砜14c热分解而形成的。电子我使用DFT方法研究了其机理。在亚硫亚胺中的消除似乎比在类似亚砜中的消除更有利于约2kcal / mol。通过单晶X射线分析建立了四种噻二嗪中的三种的晶体和分子结构。发现所有噻二嗪为4H互变异构体,杂环沿S(1)··N(4)线折叠。苯并衍生物1a形成一维N(4)-H··N(2)链,吡嗪并衍生物1c形成具有两个协同氢键的二聚体对,并且1d的晶体结构具有强C 6 F 4 ·的特征。 ··C 6 H 5四极相互作用。
Copper-promoted aerial oxidation of benzothiadiazines: access to benzothiadiazine S-oxide heterocycles
作者:Ewan R. Clark、John J. Hayward、Bryce J. Leontowicz、Muhammad U. Anwar、Melanie Pilkington、Jeremy M. Rawson
DOI:10.1039/c4dt03467h
日期:——
Aerial oxidation of benzothiadiazines selectively affords the corresponding benzothiadiazine S-oxides in the presence of Cu2+ ions. Structural studies reveal that the S-oxide appears to be a strong hydrogen-bond acceptor.
Gilchrist, Thomas L.; Rees, Charles W.; Vaughan, David, Journal of the Chemical Society. Perkin transactions I, 1983, # 1, p. 55 - 59
作者:Gilchrist, Thomas L.、Rees, Charles W.、Vaughan, David
DOI:——
日期:——
Experimental and Theoretical Studies of Fused-Ring Persistent [1,2,4]Thiadiazinyl Radicals
作者:Józef Zienkiewicz、Piotr Kaszynski、Victor G. Young
DOI:10.1021/jo0486746
日期:2004.10.1
Five persistent radicals la-le were generated by the oxidation of 4H-[1,2,4]thiadiazines 2a-2e and studied with ESR and UV-vis spectroscopy. Three of the radicals, 1a, 1d, and 1e, were generated in high yields (>90%) using either SO2Cl2/amine in toluene or AgO/K2CO3 in a toluene/MeCN mixture. Halogenated radicals 1d and le were sufficiently stable for chromatographic isolation and vacuum sublimation. The solution stability of the fluorinated 1d was measured at t(1/2) approximate to 4 months in the absence of oxygen, and le at t(1/2) approximate to 40 min in the presence of air. The crystal and molecular structures of 1d were determined by X-ray crystallography showing columns of parallel almost evenly spaced planar heterocycles connected by infinite ...N...S... chains. Cyclic voltammetry of 1d and le shows reversible reduction waves at about 0 V and irreversible oxidations at about 1.2 V. Spectral and electrochemical properties of 1 were well reproduced by DFT methods.
FINCH N.; RICCA S. JR.; WERNER L. H.; RODEBAUGH R., J. ORG. CHEM., 1980, 45, NO 17, 3416-3421
作者:FINCH N.、 RICCA S. JR.、 WERNER L. H.、 RODEBAUGH R.