Radical anions of nitrobenzothiazoles: EPR study of conjugative properties of benzothiazolyl systems

被引:6
作者
Ciminale, F [1 ]
机构
[1] Univ Bari, Dipartmento Chim, I-70126 Bari, Italy
关键词
EPR spectroscopy; radical anions; nitrobenzothiazoles; one electron reduction;
D O I
10.1016/j.tetlet.2004.06.004
中图分类号
O62 [有机化学];
学科分类号
070303 ; 081704 ;
摘要
The electrochemical reduction in DMSO of the five isomers of nitrobenzothiazole (NBTZ) gave quite persistent radical anions that could be easily characterised by EPR spectroscopy. By contrast, the chemical reduction in alkaline solution, that is by t-BuOK in DMSO or by glucose and MeOK in MeOH presented some problems with 6- and 4-NBTZ, and in the case of 2-NBTZ did not provide any detectable paramagnetic species. The internal consistency of coupling constants of the nitrobenzothiazole radical anions is in good agreement with the conjugative properties of the various benzothiazolyl systems and allows rectifying a recent EPR characterisation of 6-NBTZ radical anion. (C) 2004 Elsevier Ltd. All rights reserved.
引用
收藏
页码:5849 / 5852
页数:4
相关论文
共 20 条
[1]   ELECTRON SPIN RESONANCE STUDIES OF RADICAL ANIONS .2. AROMATIC NITRO-COMPOUNDS [J].
AYSCOUGH, PB ;
WILSON, R ;
SARGENT, FP .
JOURNAL OF THE CHEMICAL SOCIETY, 1963, (NOV) :5418-&
[2]   RING-OPENING AND CLOSING IN HETEROCYCLIC-COMPOUNDS - H-1 NUCLEAR MAGNETIC-RESONANCE STUDIES ON REACTION BETWEEN 6-NITROBENZOTHIAZOLE AND METHOXIDE ION IN DIMETHYL SULFOXIDE-METHANOL [J].
BARTOLI, G ;
CIMINALE, F ;
TODESCO, PE .
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2, 1975, (14) :1472-1474
[3]   RING-OPENING AND CLOSING IN HETEROCYCLIC-COMPOUNDS - KINETIC STUDIES ON SOLVENT EFFECTS IN REACTION BETWEEN 6-NITROBENZOTHIAZOLE AND METHOXIDE ION AT 25 DEGREESC [J].
BARTOLI, G ;
LELLI, M ;
CIMINALE, F ;
ATTANASI, O .
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2, 1977, (01) :20-24
[4]  
BARTOLI G, DIP CHIMICA ORGANICA
[5]  
BOWERS KW, 1968, RADICAL IONS, P224
[6]   KINETIC AND MECHANISTIC STUDIES OF THE REACTIONS BETWEEN 2-NITROTHIAZOLE, 2-NITROBENZOTHIAZOLE AND SOME NUCLEOPHILES [J].
FORLANI, L .
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2, 1991, (11) :1699-1702
[7]   SUBSTITUENT EFFECTS ON ELECTRON SPIN RESONANCE SPECTRA AND STABILITY OF FREE RADICALS [J].
JANZEN, EG .
ACCOUNTS OF CHEMICAL RESEARCH, 1969, 2 (09) :279-&
[8]   The oxidation of 2-aminobenzothiazoles [J].
Kirk, W ;
Johnson, JR ;
Blomquist, AT .
JOURNAL OF ORGANIC CHEMISTRY, 1943, 8 (06) :557-563
[9]   RADICAL-ANIONS OF PARA-SUBSTITUTED AROMATIC NITROCOMPOUNDS [J].
KOLKER, PL ;
WATERS, WA .
JOURNAL OF THE CHEMICAL SOCIETY, 1964, (MAR) :1136-&
[10]   Synthesis and non-linear optical and redox properties of 6-nitro-6′-piperidyl-2,2′-bisbenzothiazole:: a new type of push-pull molecules [J].
López-Calahorra, F ;
Martínez-Rubio, M ;
Velasco, D ;
Brillas, E ;
Julià, L .
TETRAHEDRON, 2004, 60 (02) :285-289