Reaction Of Pyridine N-oxides Research Articles

Palladium-catalyzed regioselective benzylation-annulation of pyridine N-oxides with toluene derivatives via multiple C-H bond activations: benzylation versus arylation.

A palladium-catalyzed cross-dehydrogenative coupling (CDC) reaction of pyridine N-oxides with toluenes has been developed that operates under mild conditions. 2-Benzylpyridines can be obtained directly by this method via a CDC reaction between unactivated toluenes and pyridine N-oxides. In addition, azafluorene N-oxides, of value for future medicinal chemistry applications, can be obtained successfully by this procedure via four tandem C-H bond activations.

Reductive acylamination of pyridine N-oxide with ethylenediamine and phenylenediamines

Reactions of pyridine N-oxide with ethylenediamine and o- and p-phenylenediamines in the presence of p-toluenesulfonyl chloride in alkaline medium lead to the formation of the corresponding N,N′-bis-(p-tolylsulfonyl)-N,N′-bis(pyridin-2-yl)diamines as a result of reductive acylamination.

Reaction of pyridine N-oxides with Grignard reagents: a stereodefined synthesis of substituted dienal oximes

Rapid addition of Grignard reagents to pyridine N-oxides under mild conditions gave stereodefined dienal oximes in good to excellent yields. This reaction provides an efficient access to substituted olefins with defined stereochemistry that are potentially of interest as bioactives themselves or as versatile synthetic intermediates.

Based-induced Conversion of N-Alkoxypyridinium Salts Bearing a Formyl Group in Their Alkoxyl Chain

Reaction of pyridine N-oxide with α-disubstituted 2-bromo-aldehydes led to the expected N-alkoxypyridinium salts which were converted to 2-(α-hydroxyacyl) pyridines on base treatment

Reactions of pyridine N-oxide with some hydroxypyrimidines in the presence of platinated palladium-carbon catalyst.

The reactions of pyridine N-oxide (1) with hydroxypyrimidine derivatives (2-7) in the presence of platinated palladium-carbon (Pd-Pt/C) catalyst were studied. 5-Hydroxypyrimidine (2), 4-hydroxypyrimidines(3 and 4) and 1-methyl-2-pyrimidinone (6) gave the corresponding dimers and 2-pyridyl derivatives by this condensation with high regioselectivity at the dehydrogenative position, while 2-hydroxypyrimidine (5) gave only the 2-pyridyl derivative. 2, 4-Dihydroxypyrimidine (7) did not react under similar reaction conditions. All products obtained these reactions are new compounds.These dimerization reactions may be useful for the synthesis of the dimers of N-heteroaromatic compounds.

Pericyclic Reactions of Pyridine N-Oxides

Pericyclic Reactions of Pyridine N-Oxides

Reaction of pyridine n-oxides with triflic anhydride: Formation of n-sulfonyloxy and dipyridinium ether salts

Pyridine and picoline-N-oxides react with (CF3SO2)2O to give N-sulfonyloxy and dipyridinium ether triflate salts.

Chemistry of heterocyclic N-oxides and related compounds. 11. Reaction of pyridine N-oxide with metal ketyls and benzophenone dianions

The reaction of pyridine N-oxide with metal ketyls of benzophenone was studied. It is shown that diphenyl(2-pyridyl)carbinol N-oxide is formed with the lithium and sodium derivatives of benzophenone, whereas diphenyl(2-pyridyl)carbinol is formed with the potassium derivative of benzophenone. Diphenyl(2-pyridyl)carbinol N-oxide is obtained in lower yields in the reaction of pyridine N-oxide with benzophenone dianions. Pyridine and 4,4′- and 2,2′-dipyridyls are simultaneously formed in all of the reactions.

Chemistry of heterocyclic N-oxides and related compounds. 10. Reaction of pyridine N-oxide with 4-methyl- and 4-phenyl-substituted hantzsch esters

The corresponding dehydrogenation products were obtained in the reaction of diethyl 1,4-dihydro-2,4,6-collidine-3,5-dicarboxylates and diethyl 1,4-dihydro-4-phenyl-2, 6-lutidine-3,5-dicarboxylate with pyridine N-oxide. The reaction with dihydrocollidine is accompanied by simultaneous demethylation in the 4 position and methylation of the pyridine ring.

ChemInform Abstract: REACTION OF AROMATIC N‐OXIDES WITH DIPOLAROPHILES. II. REACTION OF β‐ALKYLPYRIDINE N‐OXIDES WITH PHENYL ISOCYANATE

AbstractDie Reaktion der Pyridin‐N‐oxide (I) mit Phenylisocyanat (II) wird untersucht und liefert Mischungen aus den isomeren Cycloaddukten (III) und (IV) sowie den isomeren Aminen (V) und (VI), die zum Teil aus ersteren bei der Behandlung mit Alkali gebildet werden können.

Reaction of aromatic N-oxides with dipolarophiles. II. Reaction of .BETA.-alkypyridine N-oxides with phenyl isocyanate.

The reaction of β-alkylpyridine N-oxides (I) with phenyl isocyanate (II) in dimethyl-formamide at 110° gave the cycloadducts (III and IV), although it was noticed that the reaction of pyridine N-oxide with II directly affords α-anilinopyridine. The duration at elevated temperature resulted in an increased yield of the anilino derivatives, while the cycloadducts tended to decrease. The effect by using various sorts of solvents demonstrated that dimethylformamide and dimethylsulfoxide are suitable for the formation of cycloadducts.

Deoxidative substitution of pyridine N-oxides. XII. Revised structures of some tetrahydropyridines isolated from the reaction of pyridine N-oxides with mercaptans and acid anhydrides

Deoxidative substitution of pyridine N-oxides. XII. Revised structures of some tetrahydropyridines isolated from the reaction of pyridine N-oxides with mercaptans and acid anhydrides

Reactions of Pyridine N-Oxide with Enamines of N-Substituted 4-Piperidines in the Presence of an Acylating Agent

Reactions of Pyridine N-Oxide with Enamines of N-Substituted 4-Piperidines in the Presence of an Acylating Agent

Reactions of Pyridine N-Oxides with Enamines of N-Substituted 4-Piperidone in the Presence of Acylating Agents

Reactions of Pyridine N-Oxides with Enamines of N-Substituted 4-Piperidone in the Presence of Acylating Agents

Reaction of pyridine N-oxide with acetic anhydride in anisole and in benzonitrile

Reaction of pyridine N-oxide with acetic anhydride in anisole and in benzonitrile

Keten. Part X. The reaction of dimethylketen with pyridine N-oxide

The reaction of dimethylketen with pyridine N-oxide gives acetone, pyridine, 4-isopropylpyridine and a bicyclic compound for which two alternative structures are suggested, which may arise by reaction of pyridine N-oxide with an α-lactone.

Reactions of pyridine N-oxides with 3,6-dichloropyridazine

The main products of the reaction of 3,6-dichloropyridazine with 2-methylpyridine 1-oxide were 6-chloro-2-(2-pyridylmethyl)pyridazin-3(2H)-one (XII; R = H), 6-chloro-4-(2-pyridylmethyl)pyridazin-3(2H)-one (XIV; R = H), and 6-chloropyridazin-3-yl 2-pyridylmethyl ether (XVI). 2,6-Dimethylpyridine 1-oxide gave homologues corresponding to the pyridazinones (XII) and (XIV), and, in addition, 6-chloropyridazin-3-yl 2,6-dimethyl-3-pyridyl ether (XIX). No compound corresponding to the methyl ether (XVI) was isolated. The reactions are discussed in the light of earlier studies of the action of 2-bromopyridine on pyridine 1-oxide, and it is suggested that initial formation of a 1-(pyridazinyloxy)pyridinium salt is followed by loss of a proton to give an anhydro-base.

Chemistry of pyridine. VII. Tetrahydropyridines from the reaction of pyridine N-oxides with mercaptans in acetic anhydride

Chemistry of pyridine. VII. Tetrahydropyridines from the reaction of pyridine N-oxides with mercaptans in acetic anhydride

Chemistry of pyridine. VIII. Stereochemistry of tetrahydropyridines isolated from the reaction of pyridine N-oxides with mercaptans in acetic anhydride

Chemistry of pyridine. VIII. Stereochemistry of tetrahydropyridines isolated from the reaction of pyridine N-oxides with mercaptans in acetic anhydride

Donor–acceptor complexes formed by phosphoryl tricyanide, phosphoryl tri-isocyanate, and phosphorus tricyanide

Evidence is presented for the formation of phosphorus tricyanide complexes with pyridine or triphenylphosphine oxide. The formation of similar complexes play an important role in the oxygen-transfer reactions of pyridine N-oxide or dimethyl sulphoxide with phosphorus tricyanide leading to phosphoryl tricyanide. It is also concluded that the association of dimethylformamide and other substituted amides with phosphorus tricyanide involves the interaction of the cyanide group and the amide.