The Chemistry of N-Substituted Pyridinium Salts

Śliwa, Wanda; Matusiak, Grazyna; Postawka, A.

doi:10.3987/r-1985-06-1513

Cited by 26 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3 We found that the reaction of (methoxycarbo nyl)methylpyridinium iodide (1) with K 2 CO 3 and methyl diazoacetate in refluxing CHCl 3 as well as in pyridine, DMSO, or acetonitrile at 25 °C actually produced tetra methyl tetrahydropyridazine 3,4,5,6 tetracarboxylate (2), the latter being formed as a mixture of the same two isomers as those obtained by carbenic decomposition of methyl diazoacetate in refluxing pyridine. A pre liminary study of the mechanism of formation of these compounds demonstrated that the possible pathway of formation of heterocyclic structures can involve the in termediate generation of pyridinium ylides and their re actions with diazo compounds.…”

mentioning

confidence: 93%

Reactions of alkyl diazoacetates with pyridinium ylides

et al. 2005

View full text Add to dashboard Cite

Pyridinium (methoxycarbonyl)methylide generated from (methoxycarbonyl)methyl pyridinium halides under the action of K 2 CO 3 reacts with alkyl diazoacetates in CH 2 Cl 2 at 20 °C, resulting in the successive addition of three CHCOOMe fragments from the ylide to form 3,6 bis(alkoxycarbonyl) 4,5 diazaoctadienoic acid diesters. Heating of the latter in the presence of pyridine leads to their isomerization to give tetraalkyl tetrahydropyridazine tetracarboxylates in high yields. Under more drastic conditions (refluxing xylene in the pres ence of pyridine), the acyclic tetraesters undergo another transformation to form pyrrole tetracarboxylic acid esters in yields of up to 60%.

show abstract

mentioning

confidence: 93%

Reactions of alkyl diazoacetates with pyridinium ylides

et al. 2005

View full text Add to dashboard Cite

show abstract

“…The cycloimmonium ylides are very important intermediates in the synthesis of azaheterocyclic structures and ylidic polymers of specific properties [1]; they have been characterized as possessing semiconductor properties [2], analytical reactants (acido-basic indicators) [3] and pesticides [4]. However, no force field for cycloimmonium ylides and thus no parameters for the ylidic bond N + -C − are known.…”

Section: Introductionmentioning

confidence: 99%

A density functional theory derived force field for the dicyano‐pyridinium methylide

Karzazi

Vergoten

Surpateanu

1997

Elect J Theoret Chem

View full text Add to dashboard Cite

SUMMARYA Fourier transform Raman spectra of solid dicyano-pyridinium methylide is reported. Observed frequencies for normal modes are compared with those calculated from normal coordinate analysis carried on the basis of an ab initio force field for dicyano-pyridinium methylide. This force field has been deduced from ab initio calculations based on the density functional theory approach. A careful scaling of the internal force constants using correct vibrational assignments is shown to predict quite accurately our experimental vibrational frequencies and the potential energy distribution for dicyano-pyridinium methylide. Thus, a general valence force field for cycloimmonium ylides is constructed on the basis of structure and vibrational spectra of dicyano-pyridinium methylide.

show abstract