2690-17-7Relevant articles and documents
Cathodic behaviour of 1-cycloalken-1-yl phenyl sulfones. I. Competition among dimerization, cleavage, isomerization and oligomerization processes in aprotic media
Prigent, Sylvie,Cauliez, Pascal,Simonet, Jacques,Peters, Dennis G.
, p. 892 - 900 (2007/10/03)
1-Cycloalken-1-yl phenyl sulfones 1a and 1b have been studied electrochemically in aprotic media (N,N-dimethylformamide, dimethyl sulfoxide, or acetonitrile containing tetraalkylammonium salts) at a mercury electrode. Their behaviour has been compared with that of 2-norbornen-2-yl phenyl sulfone 1c. The expected cleavage reaction is accompanied by a concomitant isomerization process into allyl sulfones that is triggered by electrogenerated bases. A quantitative determination of the product distribution during controlled-potential electrolyses suggests the formation of dimers and oligomeric species, arising through a Michael addition of the sulfone anions to the activated double bond of these sulfones.
On the Mechanism of the Benzophenone-Sensitized Photolysis of 2,3-Diazabicyclohept-2-ene in the Laser Jet: Evidence for Intermolecular Triplet Diradical Reactions
Adam, Waldemar,Finzel, Ralf,Walther, Barbara
, p. 2137 - 2142 (2007/10/02)
The benzophenone-sensitized laser jet photolysis of 2,3-diazabicyclohept-2-ene (1) affords, besides the previously reported cyclopentene and housane (2), also cyclopentane, cyclopentadiene, and the dimers bicyclopent-2-en-1-yl (7), 3-cyclopentylcyclopent-1-ene (8), and 1,1'-bicyclopentyl (9).As a model reaction, the pyrolysis of dimer 8 at 600 deg C/ 20 Torr leads to the other dimers 7 and 9 together with cyclopentadiene, cyclopentene, and traces of cyclopentane.Control experiments showed that H abstraction by the cyclopentane-1,3-diyl diradical (3) from cyclohexene (as model substrate for cyclopentene) and addition to housane (2) with formation of diradical 6 are unlikely pathways.Instead, the product data available can be best explained in terms of an intermolecular disproportionation of two diradicals 3 to give the cyclopent-2-en-1-yl (4) and cyclopentyl (5) radical pair, which is subsequently converted to the observed products by in-cage and out-of-cage coupling and H transfer reactions.Such intermolecular diradical chemistry becomes feasible due to the high steady-state concentrations (ca. micromolar) generated in the laser jet.Two-photon processes take place, but are of subordinate importance. - Key Words: Laser jet/ Azoalkane/ Diradical/ Radical coupling
On the Oligomerization of Cyclic Alkenes in the Presence of Zirconium-containing Catalytic Systems
Bittrich, H.-H.,Bittrich, R.,Sass, L.,Zirz, P.,Reich, P.,Zimmermann, G.
, p. 177 - 187 (2007/10/02)
In connection with investigations on olefin metathesis we studied the reaction of cyclic olefins C5 - C8 and C12 in the presence of zirconium-containing catalytic systems in the homogeneous liquid phase.The influence of different zirconium compounds on the reaction run off and on the distribution of the reaction products was examined in the presence and the absence of Lewis acids.The reaction products could be separated and identified by a combination of distillation, chromatographical, chemical and spectrometrical methods.The results show that under the conditions mentioned a metathetic polymerization and a normal olefin oligomerization take place simultaneously.
