TY - JOUR
T1 - Synthesis, Properties, and X-ray Structure of 6-Aza-5,7,12,14-tetrathiapentacene as a Novel Polyheterocyclic Electron Donor, and Related Compounds
AU - Martí, Cristina
AU - Irurre, José
AU - Alvarez-Larena, Angel
AU - Piniella, Joan F.
AU - Brillas, Enric
AU - Fajarí, Lluís
AU - Alemán, Carlos
AU - Juliá, Luis
PY - 1994/10/1
Y1 - 1994/10/1
N2 - Two new compounds, 1-aza-2,3-dichlorothianthrene (5) and 6-aza-5,7,12,14-tetrathiapentacene (6) have been prepared by reaction of 2,3,5,6-tetrachloropyridine (4) and 1,2-benzenedithiol in dimethylformamide (DMF) in the presence of sodium bicarbonate. On the other hand, the synthesis of two known compounds, 1-azathianthrene (7) and 5,7,12,14-tetr athiapentacene (8) have been improved by using the same synthetic procedure as above, starting from 2,3-dichloropyridine and 1,2,4,5-tetrachlorobenzene, respectively. The radical cations of 6-8 have been generated in fluid solution and they are stable enough to be analyzed by electron paramagnetic resonance (EPR). The hyperfine coupling (hfc) constants in the EPR spectra have been assigned according with those from thianthrene radical cation (10), reported in the literature, and with semiempirical estimations (McLachlan method). The cyclic voltammogram of 6 exhibits a redox couple (E° = 1.07 V vs SCE) which is attributed to the oxidation to its radical cation 6•+, and a second irreversible peak (Eap = 1.25 V) which is ascribed to the formation of the unstable dication 62+. X-ray structure of 6 shows that the molecule has a stable chair-shaped conformation with an interplanar angle between benzenes and pyridine ring of 134.7(1)°. The crystal packing presents a stacking pattern and the molecules overlap showing diagonal shifts in the stack. © 1994, American Chemical Society. All rights reserved.
AB - Two new compounds, 1-aza-2,3-dichlorothianthrene (5) and 6-aza-5,7,12,14-tetrathiapentacene (6) have been prepared by reaction of 2,3,5,6-tetrachloropyridine (4) and 1,2-benzenedithiol in dimethylformamide (DMF) in the presence of sodium bicarbonate. On the other hand, the synthesis of two known compounds, 1-azathianthrene (7) and 5,7,12,14-tetr athiapentacene (8) have been improved by using the same synthetic procedure as above, starting from 2,3-dichloropyridine and 1,2,4,5-tetrachlorobenzene, respectively. The radical cations of 6-8 have been generated in fluid solution and they are stable enough to be analyzed by electron paramagnetic resonance (EPR). The hyperfine coupling (hfc) constants in the EPR spectra have been assigned according with those from thianthrene radical cation (10), reported in the literature, and with semiempirical estimations (McLachlan method). The cyclic voltammogram of 6 exhibits a redox couple (E° = 1.07 V vs SCE) which is attributed to the oxidation to its radical cation 6•+, and a second irreversible peak (Eap = 1.25 V) which is ascribed to the formation of the unstable dication 62+. X-ray structure of 6 shows that the molecule has a stable chair-shaped conformation with an interplanar angle between benzenes and pyridine ring of 134.7(1)°. The crystal packing presents a stacking pattern and the molecules overlap showing diagonal shifts in the stack. © 1994, American Chemical Society. All rights reserved.
U2 - 10.1021/jo00100a022
DO - 10.1021/jo00100a022
M3 - Article
VL - 59
SP - 6200
EP - 6207
IS - 21
ER -