THIOPHENE OLIGOMERS AS POLYTHIOPHENE MODELS .1. ANODIC COUPLING OF THIOPHENE OLIGOMERS TO DIMERS - A KINETIC INVESTIGATION

被引:100
作者
ZOTTI, G
SCHIAVON, G
BERLIN, A
PAGANI, G
机构
[1] UNIV MILAN,DIPARTIMENTO CHIM ORGAN & IND,I-20133 MILAN,ITALY
[2] CNR,CTR SPECIALI SINTESI ORGAN,I-20133 MILAN,ITALY
关键词
D O I
10.1021/cm00028a006
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The kinetics of anodic coupling to dimers of thiophene oligomers (n = 3-5), methyl protected at one alpha-terminal position, has been investigated in 1,2-dichloroethane by cyclic voltammetry and chronoamperometry. The process, second-order in oligomer concentration, is characterized by relatively high activation enthalpies (25/70 kJ mol-1) and negative activation entropies (-100/-4 J K-1 mol-1). Though activation free energies are linearly related to the inverse of the oligomer length n (the dimerization rate decreases as n is increased), the activation enthalpy and entropy for the pentameric radical cation are peculiarly high, reflecting strong electron delocalization and ring coplanarization.
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页码:430 / 436
页数:7
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共 39 条
  • [21] LARUMBE D, 1991, J ELECTROANAL CHEM, V30, P4241
  • [22] PREPARATION OF NATURALLY-OCCURRING ALPHA-TERTHIOPHENES (2,2'-5',2''-TERTHIOPHENES)
    NAKAYAMA, J
    NAKAMURA, Y
    TAJIRI, T
    HOSHINO, M
    [J]. HETEROCYCLES, 1986, 24 (03) : 637 - 640
  • [23] CHRONOAMPEROMETRIC DETERMINATION OF RATE OF DIMERIZATION OF SOME SUBSTITUTED TRIPHENYLAMINE CATION RADICALS
    NELSON, RF
    FELDBERG, SW
    [J]. JOURNAL OF PHYSICAL CHEMISTRY, 1969, 73 (08) : 2623 - &
  • [24] NYBERG K, 1973, ORGANIC ELECTROCHEMI, P705
  • [25] ELECTROCHEMICAL STUDY ON THE INITIAL-STAGES OF THE ELECTROPOLYMERIZATION OF 1-PYRENAMINE IN ACETONITRILE
    OHSAKA, T
    HIRABAYASHI, K
    OYAMA, N
    [J]. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 1986, 59 (11) : 3423 - 3429
  • [26] PHARM CV, 1989, PHOSPHORUS SULFUR SI, V46, P153
  • [27] POLY MONOTRITHIOPHENE, BITRITHIOPHENE AND TRITHIOPHENE - EFFECT OF OLIGOMER CHAIN-LENGTH ON THE POLYMER PROPERTIES
    RONCALI, J
    GARNIER, F
    LEMAIRE, M
    GARREAU, R
    [J]. SYNTHETIC METALS, 1986, 15 (04) : 323 - 331
  • [28] EFFECTS OF STERIC FACTORS ON THE ELECTROSYNTHESIS AND PROPERTIES OF CONDUCTING POLY(3-ALKYLTHIOPHENES)
    RONCALI, J
    GARREAU, R
    YASSAR, A
    MARQUE, P
    GARNIER, F
    LEMAIRE, M
    [J]. JOURNAL OF PHYSICAL CHEMISTRY, 1987, 91 (27) : 6706 - 6714
  • [29] ROSSI R, 1990, GAZZ CHIM ITAL, V120, P793
  • [30] ROSSI R, 1985, GAZZ CHIM ITAL, V115, P575