84064-95-9Relevant academic research and scientific papers
Divergent oxidative rearrangements in solution and in a zeolite: Distal vs proximal bond cleavage of methylenecyclopropanes
Ikeda, Hiroshi,Nomura, Tsuyoshi,Akiyama, Kimio,Oshima, Mitsuhiro,Roth, Heinz D.,Tero-Kubota, Shozo,Miyashi, Tsutomu
, p. 14497 - 14504 (2007/10/03)
Irradiation of 9,10-dicyanoanthracene (DCA) or p-chloranil in the presence of E-1-benzylidene-2-phenylcyclopropane (E-5) in CH2CI2 causes E-5 to undergo methylenecyclopropane rearrangement. An adduct, Z-7, between DCA and 5 firmly supports the involvement of a bifunctional trimethylenemethane radical cation. In contrast, incorporation of E-5 into HZSM-5 produces trans,trans-1,4-diphenyl-1,3-butadiene radical cation sequestered in the HZSM-5 interior, tt-8·+ @ HZSM-5, identified by ESR and diffuse reflectance spectroscopy. In addition, low yields of tt-8, its cis, trans-isomer (ct-8), and 1-phenyl-1,2-dihydronaphthalene (9) were isolated from the supernatant solution. The sharp contrast between the photoinduced electrontransfer reaction with photosensitizers in solution and the spontaneous reaction with redox-active acidic zeolite offers the prospect of further zeolite-induced regiodivergent reactions in a range of additional substrates.
Ionicity in Anionic Photoexcited States. The Effect of the Covalent Character of the Carbon-Metal Bond on the Photochemical Ring Opening of Cyclopropyl Anions
Fox, Marye Anne,Chen, Chia-Chung,Campbell, Kay A.
, p. 321 - 326 (2007/10/02)
Although 1-cyano- and 1-carbomethoxy-substituted trans-2,3-diphenylcyclopropyllithiums ring open to the corresponding allyllithiums upon photoexcitation, the analogous 1-vinyl- and 1-bromo-substituted cyclopropyllithiums do not.Shifts of the oxidative peak potential in the cyclic voltammetric scans of the photoreactive cyclopropyllithiums imply that they exist as ion pairs at low temperature in THF solution.The importance of the ionic character of the carbon-metal bond in determining the efficiency of photorearrangement is also implied by MNDO reaction path calculations.
