Synthesis and reactions of 2,6-bis[3-oxo-3-propanenitrile-2-(N,N-dimethylamino)methylene]pyridine

Abstract

The versatile multifunctional hitherto unreported 2,6-bis-[3-oxo-3-propanenitrile-2-(N,Ndimethylamino)methylene]pyridine 3 was prepared by the reaction of pyridine-2,6-bis-(3-oxo-3-propanenitrile) 2 with dimethylformamide-dimethylacetal (DMF-DMA). Several new pyrazole, isoxazole, pyrimidine, pyrazolopyrimidine, triazolopyrimidine and imidazopyrimidine derivatives have been synthesized by the reactions of 2,6-bis[3-oxo-3-propanenitrile-2-(N,Ndimethylamino)methylene]pyridine 3 with several nitrogen binucleophiles.

Reactions of 2,4-diphenyl-butadiene-1,4-sultone with some 1,2- and 1,3-nitrogen bi-nucleophiles

“…[8][9][10][11] They were used as Michael donors in reactions with electrophilic substrates, where the reaction was initiated by the attack of the NH 2 group onto an electron-deficient center followed by cyclization via addition/elimination to give fused heterocycles. 10,11 The behavior of 2,4-diphenylbutadiene-1,4-sultone (1) towards some 1,3-binucleophilic aminoazoles was investigated. Thus, treatment of 1 with 4H-1,2,4-triazol-3-amine (8) …”

“…[5][6][7] To the best of our knowledge, the reactivity of sultones, especially of 2,4-disubstituted butadiene-1,4-sultones, towards 1,2-and 1,3-binucleophiles has not yet been reported. In view of this, and in continuation of our current interest in the chemistry of 1,2-and 1,3-binucleophiles towards various types of dienophile, [8][9][10][11] the goal of the present study was the examination of the reactivity of 2,4-diphenylbutadiene-1,4-sultone towards selected 1,2-and 1,3-binucleophiles.…”

Recent advances in the synthesis and applications of 2,6-dipyrazolylpyridine derivatives and their complexes

“…6 Compound 3-bpp itself is most conveniently prepared from 2,6-diacetylpyridine using dimethylformamide dimethylacetyl as formylating agent, 48 but 3-bpp derivatives substituted at the pyrazole C5 positions can also be accessed by more conventional Claisen condensations or other acetylation procedures. 6 A number of new derivatives of this type have been prepared in the last eight years, [49][50][51][52][53][54][55][56][57][58][59][60][61][62] and This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2014 incorporation of electron-withdrawing substituents at the pyrazole C4 positions is also achievable by this method. [58][59][60] Preformed 3-bpp can be cleanly dialkylated at the pyrazole N1/N1 0 sites following deprotonation with NaH or another alkali metal-containing base (Scheme 5).…”

“…6 A number of new derivatives of this type have been prepared in the last eight years, [49][50][51][52][53][54][55][56][57][58][59][60][61][62] and This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2014 incorporation of electron-withdrawing substituents at the pyrazole C4 positions is also achievable by this method. [58][59][60] Preformed 3-bpp can be cleanly dialkylated at the pyrazole N1/N1 0 sites following deprotonation with NaH or another alkali metal-containing base (Scheme 5). [61][62][63][64][65][66][67] Chelation of the [3-bpp-2H] 2À anion by the alkali metal ion directs the regiochemistry of the reaction by protecting the alternative pyrazole N2/N2 0 alkylation sites.…”

Synthesis of some new 2,6-bis pyridines incorporating with tetra-substituted pyrazole heterocycles

“…7 On the other hand, various pyrazole derivatives were found to possess interesting pharmacological activities that include antirheumatic, anti-inflammatory, antipyretic and analgesic properties. [8][9][10] In view of these observations and in continuation of our interest in the synthesis of 2,6-disubstituted pyridines for different applications, [11][12][13][14][15] we considered it attractive to synthesize some poly substituted pyrazoles incorporated into the 2,6-pyridine moiety using 2,6-bis(ethoxycarbonyl-acetyl)pyridine (2) as starting material.…”