Aza-analogs of Stilbene with a Dipolar Character. (E)-1-Alkyl-[2-(azolyl-2-idene)etylidene]dihydropyridines and (E)-2-[2-(1-Alkyl-3-pyridinium)vinyl]azolate Inner Salts
Aza-analogs of Stilbene with a Dipolar Character. (E)-1-Alkyl-[2-(azolyl-2-idene)etylidene]dihydropyridines and (E)-2-[2-(1-Alkyl-3-pyridinium)vinyl]azolate Inner Salts
A convenient synthesis and characterization of several examples of (E)-2- [2-(1-alkyl-3-pyridinio): vinyl] benzimidazolate inner salts and (E)-1-alkyl-2(or 4)-[2- (benzimidazol-2-ylidene)ethylidene]-dihydropyridines with a betaine character is reported. Their structural aspects are discussed mainly on the basis of the H-1 NMR data and experimental dipole moment values (11.6-13.0 D). The experimental information available for (E)-1-alkyl-2(or 4)- [2- (benzimidazol-2-ylidene)ethylidene] dihydrepyridines (A <-> B) is consistent with a betaine character, and the dipolar form (B) has been shown to make an important contribution to the ground state.
Alcalde Ermitas, Dinares Immaculada, Pons Josep-Maria, Roca Tomas, J. Org. Chem, 59 (1994) N 3, S 639- 643
作者:Alcalde Ermitas, Dinares Immaculada, Pons Josep-Maria, Roca Tomas
DOI:——
日期:——
Aza-analogs of Stilbene with a Dipolar Character. (<i>E</i>)-1-Alkyl-[2-(azolyl-2-idene)etylidene]dihydropyridines and (<i>E</i>)-2-[2-(1-Alkyl-3-pyridinium)vinyl]azolate Inner Salts
作者:Ermitas Alcalde、Tomás Roca、Jean Pierre Fayet、Marie Claire Vertut
DOI:10.1246/cl.1991.2151
日期:1991.12
The first synthesis and characterization of several examples of the title compounds is described. Their physicochemical properties are discussed on the basis of the 1H NMR data and the large experimental dipole moments 11.66 to 13.0 Debye. Furthermore, all the experimental results for (E)-1-alkyl-[2-(azolyl-2-idene)-etylidene]-dihydropyridines (A↔B) favour the dipolar structure (B).