A Mechanistic Study of Halogen Addition and Photoelimination from π-Conjugated Tellurophenes
作者:Elisa I. Carrera、Anabel E. Lanterna、Alan J. Lough、Juan C. Scaiano、Dwight S. Seferos
DOI:10.1021/jacs.5b11649
日期:2016.3.2
electron-withdrawing substituents have the highest photochemical quantum efficiencies in the presence of an alkene trap, with efficiencies of up to 42.4% for a pentafluorophenyl-functionalized tellurophene. The photoelimination reaction was studied in detail through bromine trapping experiments and laser flash photolysis, and a mechanism is proposed. The photoreaction, which occurs by release of bromine radicals, is
Thermal and Photoreductive Elimination from the Tellurium Center of π-Conjugated Tellurophenes
作者:Elisa I. Carrera、Theresa M. McCormick、Marius J. Kapp、Alan J. Lough、Dwight S. Seferos
DOI:10.1021/ic402485d
日期:2013.12.2
This study introduces small molecule tellurophenes that can undergo photoreductive elimination. A tellurophene compound with strong light absorption properties and extended π-conjugation, 2,5-bis[5-(N,N′-dihexylisoindigo)]tellurophene (1), has been synthesized. Halogen oxidative addition to the tellurium center from various halogen sources gives the dibromo- (1Br2) and dichloro- (1Cl2) adducts, leading
Reaction of acetophenone hydrazones with TeCl4 in the presence of DBU in CH2Cl2 at rt gave vinyl ditellurides and tellurides, whereas 2,5-diaryltellurophenes were obtained in refluxing DMF. Interestingly, when 1,2-diphenylethanone hydrazone was used as the substrate, 3-phenylbenzotellurophene was obtained in 45% yield. The reaction would proceed through telluroketone intermediates.
Te(II)/Te(IV) Mediated C–N Bond Formation on 2,5-Diphenyltellurophene and a Reassignment of the Product from the Reaction of PhI(OAc)<sub>2</sub> with 2 TMS-OTf
作者:Antonino Aprile、Kalon J. Iversen、David J. D. Wilson、Jason L. Dutton
DOI:10.1021/acs.inorgchem.5b00537
日期:2015.5.18
the 3-position of 1,2-diphenyltellurophene via oxidation of the Te(II) center to Te(IV) using the I(III) oxidant [PhI(4-DMAP)2]2+. Spontaneous reduction of a transient Te(IV) coordination compound to Te(II) generates an electrophilic equivalent of 4-DMAP that substitutes at a C–H bond at the 3-position of the tellurophene. Theoretical and synthetic reaction pathway studies confirm that a Te(IV) coordination
An electron spin resonance study of the 2,5-diphenylchalcophene radical ions
作者:Alwyn G. Davies、Carl H. Schiesser
DOI:10.1016/0022-328x(90)85425-x
日期:1990.6
The 2,5-diphenylchalcophene radical ions (chalcogen = O, S, Se, Te) have been prepared by the action of alkali metal in 1,2-dimethoxyethane (anions), or by the action of sulphuric acid or thallium(III) trifluoroacetate in trifluoroacetic acid (TFAH) (cations), on the parent compounds. The ESR spectra of these radical ions have been interpreted as belonging to systems which are conformationally rigid