62172-88-7Relevant articles and documents
Ionic Pathways in the Photochemistry of Cyclic Sulfite Esters
White, Rick C.,Arney Jr, Benny E.,Perry, Jacob,Thompson, Nathan,Pithan, Phil M.,von Gradowski, Sebastian,Ihmels, Heiko
, p. 1656 - 1659 (2017/03/27)
The photochemistry of cyclic carbonate esters proceeds by the photochemical extrusion of carbon dioxide to give 1, 3-diradicals which produce oxiranes as well as other radical derived species. The corresponding cyclic sulfite esters, upon irradiation, give intermediates that are trapped by alcohols yet generate no oxiranes. These results are consistent with ionic intermediates.
Anellated hemicyanine dyes with large symmetrical solvatochromism of absorption and fluorescence
Hübener, Gerd,Lambacher, Armin,Fromherz, Peter
, p. 7896 - 7902 (2007/10/03)
A novel class of amphiphilic hemicyanine dyes is described where electron-pushing aniline and electron-pulling pyridinium are joined by anellated benzene rings. Enhancing the solvent polarity, the absorption band of these ANNINE dyes is shifted to the blu
Carbenes and the O-H Bond: Hydroxyalkyl-Substituted Arylcarbenes
Kirmse, Wolfgang,Kund, Klaus
, p. 2325 - 2332 (2007/10/02)
carbene (4), phenylcarbene (19), and carbene (30) have been generated by photolysis of tosylhydrazone or diazo precursors in protic solvents.These carbenes give cyclic ethers (7, 18, 33) competitively with insertion into O-H bonds of the solvent.For comparison, the analogous benzyl cations (9, 17, 31) have been generated by solvolysis or dediazoniation.The cations are more sensitive to structural variation than their carbenic counterparts: 9 does not undergo intramolecular nucleophilic substitution, in contrast to 17 and 31.These observations are explicable in terms of high barriers for rotation about aryl-cation bonds, as compared with low barriers for rotation about aryl-carbene bonds.Two major effects of the solvent (ROH) and of the base (RONa) on product formation may be distinguished: (i) protonation of the carbene (or of its precursors) in the more acidic media leads to predominantly cationic processes; (ii) deprotonation of the OH group under strongly basic conditions enhances the nucleophilicity of the oxygen, and also facilitates insertion into the α-C-H bonds of 30.