Synthesis of Some Halogen- and Nitro-substituted Nicotinic Acids and Their Fragmentation Under Electron Impact

Dyadyuchenko, L. V.; Стрелков, В. Д.; Mikhailichenko, S. N.; Zaplishny, V. N.

doi:10.1023/b:cohc.0000028626.45566.67

Cited by 8 publications

(2 citation statements)

References 2 publications

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“…To a toluene solution containing 2-chloro-4,6-dimethylnicotinic acid (2.00 g, 10.8 mmol) [55] was added thionyl chloride (1.90 g, 16.2 mmol), and the mixture was refluxed for 6 h at 80 °C. After removal of the solvent and excess thionyl chloride in vacuo, crude 2-chloro-4,6-dimethylnicotinyl chloride was obtained and used for the subsequent reaction.…”

Section: Preparation Of Nicotinamides 1a-cmentioning

confidence: 99%

Deracemization of Axially Chiral Nicotinamides by Dynamic Salt Formation with Enantiopure Dibenzoyltartaric Acid (DBTA)

et al. 2013

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Dynamic atroposelective resolution of chiral salts derived from oily racemic nicotinamides and enantiopure dibenzoyltartaric acid (DBTA) was achieved by crystallization. The absolute structures of the axial chiral nicotinamides were determined by X-ray structural analysis. The chirality could be controlled by the selection of enantiopure DBTA as a chiral auxiliary. The axial chirality generated by dynamic salt formation was retained for a long period after dissolving the chiral salt in solution even after removal of the chiral acid. The rate of racemization of nicotinamides could be controlled based on the temperature and solvent properties, and that of the salts was prolonged compared to free nicotinamides, as the molecular structure of the pyridinium ion in the salts was different from that of acid-free nicotinamides.

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Section: Preparation Of Nicotinamides 1a-cmentioning

confidence: 99%

Deracemization of Axially Chiral Nicotinamides by Dynamic Salt Formation with Enantiopure Dibenzoyltartaric Acid (DBTA)

et al. 2013

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“…The starting materials were substituted nicotinamides 1а-с, the synthesis of which has been described [11]. The amides 1а-с were converted to 3-aminopyridines 2а-с by the action of sodium hypobromite under the conditions of Hofmann amide degradation [12], which allowed to obtain the latter in 68-88% yields.…”

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confidence: 99%

Synthesis of Several Substituted Pyridine-3-Sulfonyl Chlorides, -Sulfonic Acids, and -Sulfonyl Amides*

Dyadyuchenko

Дмитриева

Nazarenko

et al. 2014

Chem Heterocycl Comp

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Diazotation of substituted 3-aminopyridines with subsequent substitution of diazo groups with sulfonyl groups in the obtained diazonium chlorides was used to synthesize the corresponding pyridine-3-sulfonyl chlorides. The conditions for this synthesis were optimized by taking into account the detailed understanding of this substitution. The synthesized pyridine-3-sulfonyl chlorides were converted to pyridine-3-sulfonic acids and -sulfonyl amides.Aromatic and heteroaromatic sulfonic acids are compounds of high importance for industry and agriculture, serving as intermediates for the synthesis of many valuable technical and pharmaceutical compounds. In particular, sulfonic acid derivatives -aryl-and hetarylsulfonyl amides find use as pharmaceuticals [1,2], plant growth regulators [3], herbicides [4], etc. These acids generally are synthesized by two methods: -sulfonation of the corresponding pyridines; -diazotation of 3-aminopyridines, followed by substitution of diazo group with sulfonyl group. In that case, intermediate pyridine-3-sulfonyl chlorides are formed, which are hydrolyzed to sulfonic acids.Direct sulfonation of pyridines can be accomplished under harsh conditions: with concentrated oleum at the temperature range of 180-230°С and catalysis by mercury salts, and is applicable to the synthesis of unsubstituted [5, 6] and monosubstituted pyridine-3-sulfonic acids [6,7].Another method for the synthesis of pyridine-3-sulfonic acids uses mild conditions and has been described primarily for the preparation of monosubstituted acids [8][9][10]. At the same time, the limited number of literature references for the synthesis of polysubstituted pyridine-3-sulfonic acids and their derivatives shows that very few studies have been performed on this topic.Our goal was to search for promising biologically active compounds in this direction through synthesis of new pyridine-3-sulfonyl chlorides as synthons for the preparation of N-substituted sulfonic acids and sulfonyl amides. _______ *Dedicated to Academician of the Russian Academy of Sciences Yu. N. Bubnov on the occasion of his 80th birthday.

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