Heterocyclic betaines. 13. Synthesis and electronic and molecular structures of methylenepyridinium and methyleneimidazolium azolate inner salts
摘要:
A convenient synthesis of several examples of betaines 3 and 4 is reported. The electronic and molecular structure of the title betaines 3 and 4 is investigated in terms of a single-crystal diffraction X-ray analysis of compound 7, spectroscopic methods, and experimental dipole moment values (12.34-15.34 D). Semiempirical molecular orbital calculations (MNDO and AM1 methods) provide a useful complementary information to the experimental results.
A convenient synthesis of several examples of betaines 3 and 4 is reported. The electronic and molecular structure of the title betaines 3 and 4 is investigated in terms of a single-crystal diffraction X-ray analysis of compound 7, spectroscopic methods, and experimental dipole moment values (12.34-15.34 D). Semiempirical molecular orbital calculations (MNDO and AM1 methods) provide a useful complementary information to the experimental results.
1-(2′-Benzimidazolylmethyl)-pyridinium ylide in the one-pot synthesis of indolizine and benzimidazo[1,2-<i>a</i>]pyridine derivatives
Abstract Four indolizine derivatives were obtained via 1,3-dipolar cycloaddition reaction of 1-(2′-benzimidazolylmethyl)pyridinium ylide with various electron-deficient alkynes. The reaction of this pyridinium N-ylide with dimethyl maleate gave an unexpected methyl 1-oxo-benzimidazo[1,2-a]pyridine-3-carboxylate. The structures of all reported compounds have been examined by X-ray crystallography and
摘要 通过1-(2'-苯并咪唑基甲基)吡啶鎓叶立德与各种缺电子炔烃的1,3-偶极环加成反应得到了四种吲哚嗪衍生物。该吡啶鎓N-叶立德与马来酸二甲酯的反应产生出乎意料的1-氧代-苯并咪唑并[1,2-a]吡啶-3-羧酸甲酯。所有报道的化合物的结构都已通过 X 射线晶体学和核磁共振光谱检查。