77083-34-2Relevant academic research and scientific papers
Efficient production of enol ether radical cations by heterolytic cleavage of β-mesylate radicals
Taxil, Elsa,Bagnol, Laurent,Horner, John H.,Newcomb, Martin
, p. 827 - 830 (2007/10/03)
(Matrix presented) α-Methoxy-β-mesyloxy radicals were produced in laser flash photolysis reactions, and yields of enol ether radical cations formed by heterolytic fragmentation of the mesylate group were determined. The mesylate heterolysis reaction is fa
Behavior of biradicals generated from a Norrish type-I reaction of 2,2- diphenylcycloalkanones. Chain-length dependence and magnetic field effects
Suzuki, Itsuko,Tanaka, Ryoko,Yamaguchi, Akinori,Maki, Shin-Ichiro,Misawa, Hiroaki,Tokumaru, Katsumi,Nakagaki, Ryoichi,Sakuragi, Hirochika
, p. 103 - 113 (2007/10/03)
The reaction course of acyl-diphenylmethyl biradicals (α-oxo-ω, ω- diphenyl-α,ω-alkanediyl biradicals), O=C↑(CH2)η-2-C↑Ph2 (3BR-η), generated from the Norrish type-I reaction of 2,2-diphenylcycloalkanones (CK- η) with various ring sizes in methanol, is switched from intramolecular disproportionation (n = 6, 7), giving a diphenylalkenal, to acylphenyl recombination (n ≥ 9), affording a cyclophane derivative. The behavior of 3BR-9 derived from CK-9 was studied in detail; the photolysis of CK-9 afforded an open-chain and a cyclic decarbonylation product together with an unsaturated aldehyde and a 4-methylene-2,5-cyclohexadienyl ketone (a pre- cyclophane). The photolysis of this ketone gave the same products that arose from the photolysis of CK-9, presenting the possibility that the decarbonylation products and a part of the aldehyde are formed as secondary products during irradiation. The magnetic field dependence of the lifetimes of 3BR-η (η = 12 and 13) generated from CK-12 and 13, respectively, was measured in methanol by means of a pulsed-laser excitation technique. The rate constants for intersystem crossing showed a maximum at a relatively low field strength, which decreased with increasing the field strength to level off to an asymptotic value at > 1.5 kG. The results show that the role of hyperfine coupling in intersystem crossing is less important in these systems, presumably because of the presence of a carbonyl oxygen and the absence of a hydrogen atom at the radical center.
Effects of chain length on behavior of biradicals generated from Norrish type I reaction of 2,2-diphenylcycloalkanones. Isolation and photochemistry of intermediate methylenecyclohexadienyl ketones
Tanaka,Suzuki,Yamaguchi,Misawa,Sakuragi,Tokumaru
, p. 3651 - 3654 (2007/10/02)
The reaction course of biradicals, O=C(↑)-(CH2)(n-2)-C(↑)Ph2, generated from Norrish type I reaction of 2,2-diphenylcycloalkanones with various ring sizes, is switched from intramolecular disproportionation (n = 6,7) to acyl-phenyl r
The use of insoluble benzoylated polystyrene beads (polymeric benzophenone) in photochemical reactions
Bourdelande, Jose Luis,Font, Josep,Sanchez-Ferrando, Francisco
, p. 1007 - 1016 (2007/10/02)
Friedel-Crafts benzoylation of 2percent-divinylbenzene (DVB) cross-linked polystyrene beads yielded insoluble polymeric analogs of benzophenone which were used as sensitizers in the photocycloaddition of cyclohexene to maleic anhydride and in the E-Z isomerization of (E)-1,3-pentadiene and methyl (E)-2,2-dimethyl-3,5-hexadienoate.In the first reaction, the use of polymer-anchored sensitizers resulted in the separation of polymer-attached by-product by simple filtration, although the yield of photoadducts was less than three quarters of that obtained when using benzophenone itself, and the recovered polymers could not be reused.In the photoisomerizations, the compositions of the photostationary states reached when using the polymeric sensitizers (now reusable) were shown to depend on the degree of functionalization of the polymers via steric hindrance to the energy transfer process.Intrapolymerically sensitized E-Z photoisomerization was also demonstrated on a polymer containing benzophenone and diene units.Photooxidation of secondary alcohols (isopropanol, cyclohexanol) to ketones and photooxygenation of 2,3-dimethyl-2-butene to 2,3-dimethyl-3-buten-2-yl hydroperoxide (in the presence of oxygen) were other reactions for which polymeric benzophenones could be used.
PHOTOCYCLOADDITION OF CYCLOHEXENE AND MALEIC ANHYDRIDE SENSITIZED BY INSOLUBLE BENZOYLATED POLYSTYRENE
Bourdelande, J. L.,Font, J.,Sanchez-Ferrando, F.
, p. 3805 - 3808 (2007/10/02)
Friedel-Crafts benzoylation of styrene - 2percent DVB copolymer beads yielded insoluble benzoylated polystyrene which was successfully used as sensitizer in the photocycloaddition of cyclohexene with maleic anhydride.
