Addition of diamines to methylthiopyridones

Hehemann, David G.; Winnik, Witold

doi:10.1002/jhet.5570310224

Cited by 25 publications

(18 citation statements)

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“…Itramolecular transamination of XIa-XId with opening of the pyridine ring leads to dihydroimidazole (tetrahydropyrimidine) derivatives XIIaXIId which undergo isomerization at the double C=C bond to adopt conformation XIІIa-XIIId which is the most favorable for subsequent intramolecular cyclization to fused 3-alkylcarbamoyl-5-benzoylpyridin-2-one derivatives VIa-VId. Unlike reactions of ethyl 5-cyano-4-methyl-2-methylsulfanyl-6-oxo-1-phenyl-1,6-dihydropyridine-3-carboxylate with ethane-1,2-diamine and propane-1,3- diamine, reported previously [12], the described recyclization of ethyl 1-alkyl-5-benzoyl-6-methylsulfanyl-2-oxo-1,2-dihydropyridine-3-carboxylates involves the ethoxycarbonyl group in the substrate, while no elimination of the alkylamino group occurs, so that the process is possible only via cleavage of the N-C 6 bond in the pyridine ring. As a result, bicyclic 5-benzoylpyridin-2-one derivatives having a carboxamide functionality can be obtained.…”

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confidence: 57%

Recyclization of ethyl 1-alkyl-5-benzoyl-6-methylsulfanyl-2-oxo-1,2-dihydropyridine-3-carboxylates into Bicyclic N-alkyl-5-benzoyl-2-oxo-1,2-dihydropyridine-3-carboxamide derivatives by the action of nitrogen-containing 1,4- and 1,5-binucleophiles

et al. 2009

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Reactions of ethyl 1-alkyl-5-benzoyl-6-methylsulfanyl-2-oxo-1,2-dihydropyridine-3-carboxylates with nitrogen-containing 1,4-and 1,5-binucleophiles (o-phenylenediamine, o-aminobenzenethiol, ethane-1,2-diamine, and propane-1,3-diamine) involved recyclization, leading to the formation of fused N-alkyl-5-benzoyl-2-oxo-1,2-dihydropyridine-3-carboxamides, diethyl 6,6′-oxybis(1-alkyl-5-benzoyl-2-oxo-1,2-dihydropyridine-3-carboxylates), and diethyl 6,6′-[ethane-1,2-diyl(or propane-1,3-diyl)diimino]bis(1-alkyl-5-benzoyl-2-oxo-1,2-dihydropyridine-3-carboxylates), depending on the reactant ratio. The sequence of formation of intermediate recyclization products was determined.We recently developed a procedure for the synthesis of ethyl 1-alkyl-5-benzoyl-6-methylsulfanyl-2-oxo-1,2-dihydropyridine-3-carboxylates Ia and Ib [1]. Unlike methods reported previously [2-4], the developed procedure ensures high selectivity and utilizes accessible initial compounds. 2-Oxo-1,2-dihydropyridines I were used as substrates in cyclocondensations with nitrogen-containing 1,2-, 1,3-, and 1,5-binucleophiles [1, 2, 5]. The reactions of dihydropyridines Іa and Ib with propane-1,3-diamine involved recyclization [5].The goal of the present work was to estimate the scope of application of the above recyclization and examine how the ratio of initial 1,2-dihydropyridin-2-one Ia or Ib and difunctional nucleophile [o-phenylenediamine (IIa), o-aminobenzenethiol (IIb), ethane-1,2-diamine (Va), and propane-1,3-diamine (Vb)] affects the reaction direction. We were also interested in elucidating the reaction mechanism (i.e., the transformation sequence and structure of intermediate products) and unambiguously determining the structure of recyclization products. Recyclizations with participation of o-phenylenediamine (IIa) and o-aminobenzenethiol (IIb), leading to the formation of benzimidazole, quinoxaline, and 1,4-benzothiazine derivatives, were the subjects of recent publications [6][7][8], which demonstrated increased interest in such reactions.Compounds Ia and Ib were found to react with nucleophiles IIa, IIb, Va, and Vb along two pathways. When the reactant ratio was 1 : 1 or 1 : 2, the products were not substituted 2H-pyran-2-ones (as we presumed previuously [5]) but mixtures of fused N-alkyl-5-benzoyl-2-oxo-1,2-dihydropyridine-3-carboxamide derivatives ІІІa-IIId or VIa-VId and diethyl 6,6′-oxybis(1-alkyl-5-benzoyl-2-oxo-1,2-dihydropyridine-3-carboxylates) IVa and IVb. The yields of compounds ІІІa-IIId, VIa-VId, and IVa, IVb were 57-70, 39-69, and 24-49%. respectively. The reactions of compounds Ia and Ib with diamines Va and Vb at a ratio of 2 : 1 led to the formation of the corresponding diethyl 6,6′-[ethane-1,2-diyl(or propane-1,3-diyl)diimino]bis(1-alkyl-5-benzoyl-2-oxo-1,2-dihydropyridine-3-carboxylates) VIIa-VIId (Scheme 1). Dihydropyridine Ia reacted with butane-1,4-diamine (Vc) to give 6,6′-(butane-1,4-diyldiimino)bis(1-alkyl-5-benzoyl-2-oxo-1,2-dihydropyridine-3-carboxylate) (VIIe) as the only product even when the amount of diamine Vc was 3 ...

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confidence: 57%

Recyclization of ethyl 1-alkyl-5-benzoyl-6-methylsulfanyl-2-oxo-1,2-dihydropyridine-3-carboxylates into Bicyclic N-alkyl-5-benzoyl-2-oxo-1,2-dihydropyridine-3-carboxamide derivatives by the action of nitrogen-containing 1,4- and 1,5-binucleophiles

et al. 2009

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“…Thus, for example, the ethoxycarbonyl group, located in the ortho position to the methylthio group, allows for various reactions with closing of a new ring. This characteristic was used in the article [17] to synthesize the pyrazolopyridine derivative ( 30 ), with the closing of the pyrazole ring by hydrazine hydrate. The mechanism of this reaction proposed in ref.…”

Section: Synthesis Of Pyrazolo[34‐b]pyridin‐6‐ones Based On Annementioning

confidence: 99%

Synthesis of Pyrazolo[3,4‐b]pyridin‐6‐ones

Komarova¹,

Makarov²,

Граник³

et al. 2012

Journal of Heterocyclic Chem

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“…Pharmacologically active bicyclic pyridones [21] are usually synthesized by cyclocondensation of ketenaminals, [22] addition of diamines to thiomethyl pyridones, [23] intramolecular Mitsunobu reactions of 2,6-difluoropyridines, [24] and the functionalization of simple bicyclic pyridones. [25] Intrigued by the structural features, we reacted 3 and 4 with different diamines in ethanol at reflux, efficiently affording bicyclic pyridones 6 in 58-88 % yields ( Table 4).…”

Section: Angewandte Chemiementioning

confidence: 99%