85562-08-9Relevant academic research and scientific papers
Enolization in Radical Cations of o-Methylacetophenone and Related Species under Cryogenic Conditions
Marcinek, Andrzej,Michalak, Jacek,Rogowski, Jacek,Tang, Weilin,Bally, Thomas,Gebicki, Jerzy
, p. 1353 - 1357 (2007/10/02)
Upon radiolytic ionization of o-methylacetophenone in low temperature matrices, the radical cation of the corresponding enol is formed.The kinetics of this process indicate a significant contribution of quantum-mechanical tunnelling in the hydrogen atom transfer.The same species is also formed by ionizing 1-methyl-1,2-dihydrobenzocyclobutenol but the composition of the rotameric mixture of enol radical cations is different in this case.Analogous experiments with 5,8-dimethyl-1-tetralone demonstrate that enol radical cations are stable in their Z-conformation under cryogenic conditions in contrast to the corresponding neutrals.
TRAPPING OF PHOTOENOLS FROM o-TOLUALDEHYDES IN GAS MATRICES. DEPENDENCE OF PHOTOENOL FORMATION ON THE NATURE OF THE CARBONYL FUNCTION
Gebicki, J.,Krantz, A.
, p. 1623 - 1628 (2007/10/02)
o-Methylbenzaldehyde (1) and o-methylacetophenone (2), matrix-isolated in Ar, N2, Xe, or carbon monoxide, were irradiated with u.v. light.In contrast to the ketone (2) which was unreactive, the benzaldehyde gave a photoenol in all gas matrices.Irradiation of 2,5- or 2,4-dimethylbenzaldehyde (9) and (10), respectively, also produced photoenols under the above conditions.In propan-2-ol under cryogenic conditions, o-methylacetophenone (2) can be photoisomerized to an enol, probably the consequence of stabilization of the Z-enol by hydrogen bonding. 5,8-Dimethyltetralone (11) does not give a photoenol in gas matrices, although it is reported to give one at 77 K in EPA.It is proposed that cage effects in gas matrices can significantly alter rates of internal rotation and are determinants in the production of E-enols in this environment.I.r. spectral evidence for photoenols is presented for the first time.
