Synthesis and reactions of 2,3-dimethylfuro[3,2-c]pyridines (original) (raw)

Synthesis of a New Series of Pyridine and Fused Pyridine Derivatives

Molecules, 2012

The reaction of 4-methyl-2-phenyl-1,2-dihydro-6-oxo-5-pyridine-carbonitrile (1) with arylidene malononitrile afforded isoquinoline derivatives 2a,b. 6-Chloro-4methyl-2-phenyl-5-pyridinecarbonitile (3) obtained by chlorination of compound 1 with phosphoryl chloride was converted into 6-amino-4-methyl-2-phenyl-5-pyridinecarbonitrile (4) and 6-hydrazido-4-methyl-2-phenyl-5-pyridinecarbonitrile (5) in good yield, through reactions with ammonium acetate and hydrazine hydrate, respectively. Treatment of 4 with ethyl acetoacetate, acetic anhydride, formic acid, urea and thiourea gave the corresponding pyrido [2,3-d] pyrimidine derivatives 7-10a,b. A new series of 6-substituted-4-methyl-2phenyl-5-pyridine carbonitriles 11-13 has been synthesized via reaction of 4 with phenyl isothiocyanate, benzenesulphonyl chloride and acetic anhydride. Treatment of 4 with malononitrile gave 1,8-naphthyridine derivative 14. The reactivity of hydrazide 5 towards acetic acid, phenylisothiocyanate and methylacrylate to give pyrazolo-[3,4-b]-pyridine derivatives 15-17 was studied. Treatment of 5 with acetic anhydride, phthalic anhydride and carbon disulphide gave pyridine derivatives 18,19 and 1,2,4-triazolo-[3,4-a]-pyridine derivative 20.

New routes to polyfunctionally substituted pyridine, pyridopyridine, quinoline, and pyridazine derivatives

Archiv der Pharmazie, 1991

The pyridine derivatives 4 and 10 are obtained by condensing paminocrotononieile (la) with malononib'ile. Compound 4 affords the pyridylpyridadne NitrUe in der Heterocyden-Synthese: Neue Wege zu polyfunktiond substitulerten Pyrldinen, Pyrldopyridinen, Chinolinen und Pyrldazlnen 7 on coupling with aryldiazonium salts. The reaction of la with cyan* thioacemide affords which the ae,,,,[2,34iP~h 13 on treatbensylidenemalononite (14). A variety of new pyridines. cyclohexadiene. and pyridopyridine derivatives wen obtained from d o n of2-~l-propene-l,1,3-tricarbonieille (it,) and diethyl 3-amino-2cyanopent-2-enedioate. (lc) with Mlcht-systems. Reaction of l b with acrylonib'ile afforded an acyclic diadduct 25 which could be c y c l i to the aminoquinolhe 26. Die Wdine 4 und 10 wurden durch Kondensation von &Aminocrotonnitril pyridazin 7 durch Kupplung mit Diazoniumsalzen-Reaktion von la mit ~O t h i o a c e t a m i d lief& u. das seinerseits Illit Phv'bom zu dm menot23-blpyridm 13 re@* Das Pyrido[23-blpyridin 15 enwht u mit B e m y l i d e n-m a l o d t. zahlniche new Pyridine, Cyclohexadiene und Pyridopyridine entstanden durch Reaktion von 2-Amino-l33-tricyanopropen (lb) bzw. dem Diethylester der ~A m i n o-~x y m e t h y l-a c r y I~ (lc) mit cgfhngesilaigten Carbonylverbiiungen. Die U m s e m g von l b mit Acrylnitril fIUute zu einem Diaddulct 25. das m Aminochinolin 26 zylclisien wurde.

Synthesis, X-ray and spectroscopic analysis of some pyridine derivatives

Journal of Molecular Structure, 2010

Three pyridine derivatives, 4-(methoxymethyl)-6-methyl-2-oxo-1,2-dihydropyridine-3-carbonitrile (1), 4-(methoxymethyl)-6-methyl-5-nitro-2-oxo-1,2-dihydropyridine-3-carbonitrile (2) and 4-(methoxymethyl)-1,6-dimethyl-2-oxo-1,2-dihydropyridine-3-carbonitrile (3) have been synthesized, and their structural features have been studied by IR and electronic spectroscopy. The optical properties were investigated by UV-vis absorption and fluorescence spectroscopy. Fluorescence spectra of compounds have been recorded in two protic and two aprotic solvents in the range of 200-600 nm. The effects of substituents on the emission spectra of these compounds are interpreted. The structures of compounds 2 and 3 were also confirmed by single crystal X-ray diffraction method.

A New Approach for the Synthesis of Some Pyridine and Pyridone Derivatives

Zeitschrift für Naturforschung B, 1983

Both visnaginone and khellinone react with malononitrile, ethyl cyanoacetate or cyanoacetamide in presence of ammonium acetate to give substituted furobenzopyrans or furobenzopyridones. However, the reaction of visnaginone and khellinone with aldehydes, and malononitrile in presence of ammonium acetate leads to the formation of the corresponding 2-amino-4,6-disubstituted pyridine 3-carbonitriles. The latter compounds are also obtained by treating the respective chalcones with malononitrile and ammonium acetate. 3-Substituted 1,3-diketobutyrates form with malononitrile or with cyanoacetamide and ammonium acetate the 2-amino-4,6-disubstituted pyridine-3-carbonitriles or the 4,6-di-substituted cyanopyridones, respectively

General Synthetic Approach to 4-Substituted 2,3-Dihydrofuro[2,3-b]pyridines and 5-Substituted 3,4-Dihydro-2H-pyrano[2,3-b]pyridines

Synlett, 2009

General Synthetic Approach to 4-Substituted 2,3-Dihydrofuro[2,3-b]pyridines and 5-Substituted 3,4-Dihydro-2H-pyrano[2,3-b]pyridines D i h y d r o f u r o -a n d D i h y d r o p y r a n o [ 2 , 3b ] p y r i d i n e s Abstract: An efficient strategy for the synthesis of functionalised 2,3-dihydrofuro[2,3-b]pyridines and 3,4-dihydro-2H-pyrano[2,3b]pyridines is reported. The strategy is based on an intramolecular inverse-electron-demand Diels-Alder reaction starting from 1,2,4triazines appropriately functionalised with alkynes, followed by various cross-coupling reactions (Suzuki, Stille, and Sonogashira).

Synthesis, Complex Compounds and Antimicrobial Activity of Some Derivatives of Furo[3,2-C]Pyridine and Their Starting Compounds

Nova Biotechnologica et Chimica, 2012

Synthesis, Complex Compounds and Antimicrobial Activity of Some Derivatives of Furo[3,2-C]Pyridine and Their Starting CompoundsSome [3,2-c]pyridine derivatives were synthesized. 3-(Furan-2-yl)propenoic acid (1a) was prepared from furan-2-carbaldehyde under the Perkin's conditions. Obtained acid was converted to the corresponding azide3, which in turn was cyclized to give furo[3,2-c]pyridin-4(5H)-one (4a). The reaction of pyridone4awith phosphorus oxychloride rendered the chloroderivative7a, which was treated in the condition of Suzuki coupling reaction with boronic acid to give 4-phenylfuro[3,2-c]pyridine (8e) and an unexpected product10. Some title compounds have shown moderate to good antimicrobial activity against tested bacteriaXanthomonas sp., Erwinia amylovora, and filamentous fungiPyrenophora avenae, Fusarium graminearum.

Synthesis of dihydrofuro[2,3- b ]pyridines by the reaction of 2-amino-4,5-dihydro-3-furancarbonitriles with α,β-unsaturated carbonyl compounds

Journal of Heterocyclic Chemistry, 2002

The reactions of 2-amino-4,5-dihydro-3-furancarbonitriles 1a-d with α,β-unsaturated carbonyl compounds in the presence of sodium ethoxide (0.1 equivalent) gave the corresponding Michael adducts 2a-d, 3a-d and 4a-d. Compounds 2a-d and 3a-c reacted with sodium alkoxide (1 equivalent) to yield the corresponding 7a-alkoxyhexahydrofuro[2,3-b]pyridines 5a-d, 6a-d, 7a-c and 8a-c. Treatment of 5a-d, 6a-d, 7a-c and 8a-c with potassium tert-butoxide produced the corresponding dihydrofuro[2,3-b]pyridines 9a-d and 10a-c. The reaction of 4a-c with sodium ethoxide (1 equivalent) afforded the corresponding dihydrofuro[2,3-b]pyridines 11a-c.

Synthesis of Some Novel 4-(Furan-2-yl)-5,6-dimethylpyridines

in Wiley Online Library (wileyonlinelibrary.com). N-2-amino-4-(furan-2-yl)-5,6-dimethylnicotinonitrile (4) was utilized as key intermediate for the synthesis of some new, pyridopyrimidine, benzo[1,5][g]oxazocine, naphthoquinone, and isoindole derivatives. The structures of the newly synthesized compounds were confirmed by elemental analysis, IR, 1 H-NMR, and mass spectral data.