5849-23-0Relevant academic research and scientific papers
An efficient photo-SET-induced cleavage of dithiane-carbonyl adducts and its relevance to the development of photoremovable protecting groups for ketones and aldehydes
McHale, William A.,Kutateladze, Andrei G.
, p. 9924 - 9931 (1998)
Irradiation of dithiane-aldehyde/ketone adducts in the presence of benzophenone leads to C-C bond cleavage regenerating the carbonyl compounds. It is established that the mechanism of this reaction involves photochemically induced single electron transfer from the dithiane moiety to the excited molecule of ET-photosensitizer, accompanied by mesolytic C-C cleavage in the generated cation-radical, which is assisted by the anion- radical of benzophenone. This mechanism is confirmed by a Hammett plot study of the cleavage in the dithiane adducts of substituted aromatic aldehydes and a deuterium kinetic isotope effect study. Ab initio computations at UHF/6- 31G* and MP2/6-31G* levels of theory in conjunction with self-consistent reaction field (self-consistent isodensity-polarized continuum model), to account for the solvent effect, also support the experimental findings. The reaction is most efficient for protection of aromatic aldehydes and ketones and aliphatic ketones, and is a novel method for protecting carbonyl functionalities with a photoremovable group.
Photochemically amplified detection of molecular recognition events: An ultra-sensitive fluorescence turn-off binding assay
Gustafson, Tiffany P.,Metzel, Greg A.,Kutateladze, Andrei G.
supporting information; experimental part, p. 4752 - 4755 (2011/08/08)
Amplified fluorescence quenching methodology based on massive autocatalytic photo-unmasking of a dual function sensitizer-quencher is developed and adopted for photoassisted ultra-sensitive detection of molecular recognition events. The resulting binding
Acid-induced rearrangement reactions of -hydroxy-1,3-dithianes
Krohn, Karsten,Cludius-Brandt, Stephan
experimental part, p. 1344 - 1348 (2010/07/06)
Secondary benzylic or aliphatic -hydroxydithianes 1a-c rearrange to -thioketones when treated with acid. Related tertiary alcohols 1d-g eliminate to dithioketene ketals (e.g., 2d), which are ring-opened to thiols in some cases (1e, 1f). Allylic -hydroxydi
Externally sensitized mesolytic fragmentations in dithiane-ketone adducts
Gustafson, Tiffany P.,Kurchan, Alexei N.,Kutateladze, Andrei G.
, p. 6574 - 6580 (2007/10/03)
The apparent activation enthalpies, ΔH≠, for externally sensitized mesolytic fragmentations in benzophenone-dithiane adducts were obtained in variable temperature photolyses and compared with DFT activation barriers calculated for β-scission in the corresponding oxygen-centered radicals. The results of these experimental and theoretical studies further support the mechanism in which deprotonation of the hydroxy-group, in the transient cation radical, is coupled with intramolecular electron transfer furnishing the O-centered radical, which subsequently fragments. The quantum yields of fragmentation increase for higher alkyl substituted dithiane adducts.
Asymmetric oxidation of 1,3-dithianes to 1,3-dithiane 1-oxides
Watanabe, Yoshihiko,Ohno, Yohjiro,Ueno, Yoshio,Toru, Takeshi
, p. 1087 - 1093 (2007/10/03)
Oxidation of 2-(1-hydroxy-1-methylethyl)-1,3-dithiane with the Sharpless reagent has been examined under various reaction conditions. Oxidation of 2-(1-hydroxy-1-methylethyl)-1,3-dithiane with Ti(OPri)4-diethyl L-(+)-tartrate-tert-bu
