6921-50-2Relevant academic research and scientific papers
Visible-Light-Induced Nickel-Catalyzed Negishi Cross-Couplings by Exogenous-Photosensitizer-Free Photocatalysis
Abdiaj, Irini,Fontana, Alberto,Gomez, M. Victoria,de la Hoz, Antonio,Alcázar, Jesús
supporting information, p. 8473 - 8477 (2018/04/30)
The merging of photoredox and transition-metal catalysis has become one of the most attractive approaches for carbon–carbon bond formation. Such reactions require the use of two organo-transition-metal species, one of which acts as a photosensitizer and t
Photochemical behavior of cyclopropyl-substituted benzophenones and valerophenones
Creary, Xavier,Hinckley, Jenifer,Kraft, Casey,Genereux, Madeleine
, p. 2062 - 2071 (2011/05/28)
p-Cyclopropylbenzophenone, 20, gives no photoreduction when irradiated in i-PrOH solvent. This is a general phenomenon and a number of cyclopropyl-substituted benzophenones, including 4-(endo-6-bicyclo[3.1.0]hexyl) benzophenone, 19, 4-(cis-2,3-dimethylcyclopropyl)benzophenone, 21, 4-(cis-2-vinylcyclopropyl)benzophenone, 22, and 4-(endo-7-bicyclo[4.1.0]hept-2- enyl)benzophenone, 23, also fail to undergo photoreduction. Instead these latter compounds undergo cis-trans isomerization when irradiated. A mechanism involving formation of an (n, π*) triplet, which subsequently fragments the strained cyclopropane bond to give a lower energy and unreactive open triplet, has been suggested. p-Cyclopropylvalerophenone, 25, and p-(endo-6-bicyclo[3.1.0]hexyl)valerophenone, 24, also undergo photoisomerization and fail to undergo the Norrish Type II photoreactions. Triplet energy dissipation by fragmentation of the cyclopropane bond is also proposed. In addition to the Norrish Type II reaction, p-cyclobutylvalerophenone, 27, undergoes a photofragmentation to give ethylene and p-vinylvalerophenone, 60, by an energy dissipation mechanism involving a 1,4-biradical derived from cyclobutane bond fragmentation.
