Thermal and photochemical transformations of tetraphenyl-p-dioxin and tetraphenyl-p-dithiin

Lahiri, S. K.; Dabral, V.; Bhat, V. V.; Jemmis, Eluvathingal D.; George, M. V.

doi:10.1007/bf03046647

Cited by 14 publications

(2 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The total yields of benzil at high conversion never reach a 2:1 molar ratio with respect to the initial amount of 1, though they systematically exceed a 1:1 ratio. 3 The difference can be largely accounted for by the formation of phenyl benzoate via the oxidation of benzil in benzene medium. It may be mentioned in this connection that the photolysis of benzil in different solvents such as cyclohexane, 2-propanal, and cumene has been studied earlier by Bunburry and co-workers.12,13 They have observed that a variety of products are formed in these reactions.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Photochemistry and photooxidation of tetraphenyl-p-dioxin

George¹,

Kumar²,

Scaiano³

1979

J. Phys. Chem.

View full text Add to dashboard Cite

Laser flash photolysis studies of tetraphenyl-p-dioxin have led to the characterization of its triplet state. The T-T absorption spectra shows maxima at 350 and 545 nm; the triplet has a lifetime of 535 ns in methanol and can be quenched by di-ieri-butyl nitroxide, paraquat dications, oxygen, and di-tert-butyl selenoketone. The interaction of the triplet with oxygen leads to the formation of singlet oxygen which in turn reacts with the title compound to yield benzil.

show abstract

Section: Discussionmentioning

confidence: 99%

“…In our earlier studies3 on the thermal and photochemical transformation of tetraphenyl-p-dioxin (1), we have suggested that the transformations of 1 involve the biradical intermediate 2, which then leads to benzil (3), and minor amounts of tolan (4), Scheme I.…”

Section: Introductionmentioning

confidence: 99%

Photochemistry and photooxidation of tetraphenyl-p-dioxin

George¹,

Kumar²,

Scaiano³

1979

J. Phys. Chem.

View full text Add to dashboard Cite

show abstract

Additionsreaktionen von 2‐Thiazolin‐5‐thionen mit Acetylenen Vorläufige Mitteilung

Jenny¹,

Obrecht²,

Heirngartner³

1982

Helvetica Chimica Acta

View full text Add to dashboard Cite

SummaryThe reaction of the 2-thiazolin-5-thiones 1 and 5, respectively, with acetylene carboxylates yields mainly 1,4-dithiafulvenes of type 3. In the presence of the acetylenic compounds, the 1,4-dithiafulvenes undergo an isomerization to give the corresponding 2,3-dihydrothiophene-2-thiones 4.Vor kurzem haben wir uber eine einfache Synthese von 4,4-disubstituierten 2-Phenyl-2-thiazolin-5-thionen berichtet [ 11. Im Rahmen von Studien zur Reaktivitat dieser bisher nicht untersuchten Verbindungsklasse sind u. a. thermische Reaktionen rnit Acetylenen, Olefinen und 1,3-dipolaren Verbindungen durchgefuhrt worden. Einige Ergebnisse der Reaktionen rnit Acetylenen sollen hier kurz wiedergegeben werden4).Umsetzungen von Acetylenen mit S-Heterocyclen, die das Strukturelement -C(S)-Senthalten, d.h. mit Verbindungen vom Typ a (Schema I), sind vonKorrespondenzautor. 4,Eine vollstandige Mitteilung sol1 in dieser Zeitschrift erscheinen. Teil der geplanten Dissertation von Ch. Jenny.Fur 1,3-dipolare Cycloadditionen an 2-Thiazolin-Sthione s.

show abstract

Vergleich der thermischen, photochemischen und massenspektrometrischen Fragmentierung von Schwefelheterocyclen mit cis‐Dithioethylenstruktur

Fanghänel

Poleschner

1981

J. Prakt. Chem.

View full text Add to dashboard Cite

Comparison of the Thermal, Photochemical and Mass Spectrometric Fragmentation of Sulphur Heterocycles with cis‐Dithioethene‐Structure The mass spectrometric primary fragmentation of 3‐methylthio‐1,4,2‐dithiazines 1, 1,4‐dithiins 2, 2,3‐dihydro‐1,4‐dithiin‐2‐ones 4, 1,3‐dithiole‐2‐ones 5, 2‐imino‐1,3‐dithioles 6 and 1,3‐dithiole‐2‐thiones 7 is compared with their thermolytical and photochemical reaction. In the mass spectra an intense peak of the dithiete radical ion is observed, if in the compounds an energetically favourable neutral molecule is preformed: in 1 methyl rhodanide, in 3 ethene, in 4 ketene, in 5 carbon monoxide and in 6 hydrogen cyanide. The substances 1, 3–6 – with the restriction by 3 – yield photochemically the dithiete, too. The photolysis of dithiazines 1 is wave length dependent. Mass spectrometrically, thermally and photochemically the dithiins 2 form thiophenes. The dithiolethiones 7 decompose mass spectrometrically and thermally into carbon disulfide, sulfur and ethynes, but photochemically they form tetrathiafulvalenes. The fragmentation of the compounds 1–6 is analogous in mass spectrometry and photolysis; 2, 3, 5 and with reservation 1 show similar mass spectrometric, thermal and photochemical reactivity. Possible reasons for these analogies are discussed. The dithietes, generated by photolysis of the compounds 1, 4, 5 or 6 react with iron penta‐, nickel tetra‐, molybdenum hexa‐ and tungsten hexacarbonyl in preparative scale to the corresponding dithiolene complexes.

show abstract

Thermal and photochemical transformations of tetraphenyl-p-dioxin and tetraphenyl-p-dithiin

Cited by 14 publications

References 24 publications

Photochemistry and photooxidation of tetraphenyl-p-dioxin

Photochemistry and photooxidation of tetraphenyl-p-dioxin

Additionsreaktionen von 2‐Thiazolin‐5‐thionen mit Acetylenen Vorläufige Mitteilung

Vergleich der thermischen, photochemischen und massenspektrometrischen Fragmentierung von Schwefelheterocyclen mit cis‐Dithioethylenstruktur

Contact Info

Product

Resources

About