19817-09-5Relevant articles and documents
Selective synthesis of 1,1'-binaphthalene derivatives by oxidative coupling with TiCl4
Doussot, Jo?l,Guy, Alain,Ferroud, Clotilde
, p. 2545 - 2547 (2007/10/03)
Oxidative coupling of naphthalene compounds with TiCl4 in nitromethane under mild conditions gives symmetrical 1,1'-binaphthyls in good yields. The method is particularly useful when applied to substrates with electron donating groups. (C) 2000 Elsevier Science Ltd.
Intramolecular Binaphthyl Formation from Radical Cations of Tri-1-naphthyl Phosphate and Related Compounds in Photoinduced Electron-Transfer Reactions Sensitized by 9,10-Dicyanoanthracene
Nakamura, Mitsunobu,Dohno, Reizo,Majima, Tetsuro
, p. 6258 - 6265 (2007/10/03)
The photoinduced electron transfer of tri-1-naphthyl phosphate and related compounds sensitized by 9,10-dicyanoanthracene (DCA) in acetonitrile produces 1,1′-binaphthyl and the corresponding biaryl. The quenching rate constant of the DCA fluorescence is calculated to be equal to the diffusion-controlled rate constant from the Stern-Volmer analysis and the fluorescence lifetime measurement. The free energy change calculated from the redox potentials and excitation energy of the singlet excited DCA indicates that the quenching process occurs exergonically to give the tri-1-naphthyl phosphate radical cation and DCA radical anion through electron transfer from tri1-naphthyl phosphate to the singlet excited DCA at the diffusion-controlled rate. On the basis of spectroscopic and kinetic studies with laser flash photolysis, pulse radiolysis, and γ-radiolysis, the radical cation of tri-1-naphthyl phosphate forms an intramolecular π-dimer radical cation with face-to-face interaction between the two naphthyl groups within 8 ns of the electron pulse. The 1,1′-binaphthyl radical cation is eliminated at the rate constant of kr = 5.3 × 105 s~: from the intramolecular π-dimer radical cation. Branching ratios of the reaction pathways are estimated for the reactive intermediates such as the tri-1-naphthyl phosphate radical cation and its intramolecular π-dimer radical cation from the rate constants and quantum yields. The electron-withdrawing character of the P(O) group in the O-P(O)-O spacer is responsible for the elimination of the binaphthyl radical cation. The DCA-sensitized photoinduced electron-transfer reaction of the tri-1-naphthyl phosphate is compared with the direct photoreaction.
Thermal and photochemical decomposition pathways of trinitromethylarenes. part II. The effects of ethanol on the photolysis reactions of some alkoxy- and dialkoxyarenes in the presence of tetranitromethane. enhancement of adduct and trinitromethyl substitution product formation
Butts, Craig P.,Eberson, Lennart,Hartshorn, Michael P.,Persson, Ola
, p. 718 - 732 (2007/10/03)
The photolysis of the charge transfer (CT) complex of tetranitromethane with 1-methoxynaphthalene, 1,4-dimethoxybenzene, 1,2-dimethoxybenzene, 1,2-methylenedioxybenzene or 2-methylanisole is reported for dichloromethane, acetonitrile, dichloromethane-ethanol and acetonitrile-ethanol solvent systems. The effects of adding ethanol (8% v/v ? 1.4 mol dm-3) to dichloromethane or acetonitrile as reaction solvents include: (i) the stabilization of alkoxytrinitro-methylarenes, thus reducing their normal tendency for decomposition according to ArC (NO2)3→ArCOOH→ArNO2, (ii) a reduction in the nucleophilicity of trinitromethanide ion, and (iii) changes in the regioselectivity of trinitromethanide ion attack on the radical cations of alkoxyaromatic compounds away from attack ipso to the alkoxy substituent. Adducts are also stabilized, as shown by the photolysis of the CT complex of 1,4-dimethoxybenzene-tetranitromethane in dichloromethane-ethanol (8% v/v) which gives the epimeric 1,4-dimethoxy-3-nitro-6-trinitromethylcyclohexa-1,4-dienes and 1,4-dimethoxy-2-trinitromethylbenzene, in addition to 1,4-dimethoxy-2-nitrobenzene. The adducts are detected also among the products of photolysis reactions in neat dichloromethane or acetonitrile. Acta Chemica Scandinavica 1997.