7516-31-6

Usage

Synthesis Reference(s)

Tetrahedron, 27, p. 379, 1971 DOI: 10.1016/S0040-4020(01)90708-2

Upstream product

• 591-78-6 n-hexan-2-one 
• 100-58-3 phenylmagnesium bromide 
• 78526-27-9 4'-Butylsulfanyl-2,6-dimethyl-4'H-[1,1']bipyridinyl-4-one 
• 76639-06-0 2,6-Dimethyl-4'-(2-oxo-propyl)-4'H-[1,1']bipyridinyl-4-one 
• 78526-28-0 4'-Cyclohexylsulfanyl-2,6-dimethyl-4'H-[1,1']bipyridinyl-4-one 
• 71831-53-3 4'-(3,3-Dimethyl-2-oxo-butyl)-2,6-dimethyl-4'H-[1,1']bipyridinyl-4-one 
• 78526-31-5 2,6-Dimethyl-4'-phenylsulfanyl-4'H-[1,1']bipyridinyl-4-one 
• 71831-52-2 2,6-Dimethyl-4'-(4-methyl-2-oxo-pentyl)-4'H-[1,1']bipyridinyl-4-one 
• 79756-96-0 (2',6'-Dimethyl-4'-oxo-4H,4'H-[1,1']bipyridinyl-4-yl)-acetic acid ethyl ester 
• 71831-63-5 4'-Benzylsulfanyl-2,6-dimethyl-4'H-[1,1']bipyridinyl-4-one 
• 71831-66-8 4'-(4-Chloro-phenylsulfanyl)-2,6-dimethyl-4'H-[1,1']bipyridinyl-4-one 
• 76639-28-6 2,6,3'-Trimethyl-4'-(2-oxo-2-phenyl-ethyl)-4'H-[1,1']bipyridinyl-4-one 
• 79756-97-1 (2',6'-Dimethyl-4'-oxo-4H,4'H-[1,1']bipyridinyl-4-yl)-acetic acid tert-butyl ester 
• 71831-78-2 2,6-Dimethyl-4'-(3-methyl-2-oxo-cyclohexyl)-4'H-[1,1']bipyridinyl-4-one 

Downstream Products

• 108-48-5 2,6-dimethylpyridine 
• 3512-75-2 4-chloro-2,6-lutidine 
• 13603-45-7 2,6-dimethyl-4-hydroxy-3-nitropyridine 
• 86775-90-8 (2,6-dimethyl-pyridin-4-yl)-phenyl-amine 
• 138642-53-2 2,6-dimethyl-3-formyl-4(1H)-pyridone 
• 31872-55-6 2,6-dimethyl-3,5-dinitro-4-pyridinol 
• 122957-45-3 2,6-dimethyl-3-nitro-4(1H)-pyridone 
• 88545-07-7 3-chloro-2,6-dimethyl-4(1H)-pyridinone 
• 909848-16-4 5-chloro-2,6-dimethyl-6'-({4-[(trifluoromethyl)oxy]phenyl}oxy)-3,3'-bipyridin-4(1H)-one 
• 111079-37-9 4-chloro-2,6-dimethyl-3-phenylethynylpyridine 
• 111079-38-0 4,6-dimethyl-2-phenylthieno<3,2-c>pyridine 
• 15513-48-1 4-chloro-2,6-dimethyl-3-nitropyridine 
• 116387-98-5 2-(2,6-Dimethyl-pyridin-4-yloxy)-1-phenyl-ethanone 
• 138677-38-0 2,6-Dimethyl-4-[2'-(2-trityl-2H-tetrazol-5-yl)-biphenyl-4-ylmethoxy]-pyridine-3-carbaldehyde 

Relevant academic research and scientific papers

Synthetic Applications of N-N Linked Heterocycles. Part 12. The Preparation of 4-Alkylthio- and 4-Arylthio-pyridines by Regiospecific Attack of Thioalkoxide Ions on N-(4-Oxopyridin-1-yl)pyridinium Salts

Thiolate ions add regiospecifically to N-(4-oxopyridin-1-yl)pyridinium salts (2)-(7) to give in good to excellent yields only the 1,4-dihydropyridine adducts (8)-(13), regardless of whether or not the pyridone moiety carries substituents for sterically shielding the 2- and 6-positions of the pyridinium ring.The addition is believed to be thermodynamically controlled.Decomposition of the dihydro-adducts under free-radical conditions, or by pyrolysis, gives good yields of pyridin-4-yl thioethers (14) and (16) though the reaction failed with the 2-methyl adducts (9).An improved synthesis of 6-methyl-4-oxopyran-2-carboxylic acid is also described.

Synthetic Applications of N-N Linked Heterocycles. Part 14. The Preparation of α-(4-Pyridyl)esters and α-(4-Pyridyl)nitriles by Regiospecific Attack of Ester and Nitrile Anions on Pyridinium Salts

Reactions between N-(2,6-dimethyl-4-oxopyridin-1-yl)pyridinium tetrafluoroborate (1) and lithio-derivatives of esters and nitriles give only low yields of 1,4-dihydro-adducts (3) and (7) due apparently to competing proton abstraction from the pyridone methyl groups.This limitation with salt (1) appears only with C-H acids of pKa > 20.Decomposition of the adducts under free-radical conditions yields α-(4-pyridyl)-esters (4) and -nitriles (8) essentially quantitatively.The same pyridyl-esters and -nitriles may be prepared conveniently in good overall yields by the reaction between the appropriate lithium salts and N-triphenylmethylpyridinium salts.The scope and limitations of the method are discucced. 2-Methyl-N-triphenylmethylpyridinium tetrafluoroborate is reported for the first time.

Synthetic Applications of N-N Linked Heterocycles. Part 10. Preparation of Novel N-N Linked Biheteroaryl Monocations, their Reactions with Nucleophiles, and Electrophilic Reactions of some Dihydro-derivatives

Novel N-N linked biheteroaryl monocations are prepared from N-aminopyridinium, -quinolinium, or -isoquinolinium salts, with dehydroacetic acid, cyclic anhydrides, hexane-2,4-dione, or the benzoxazinone (15).Reactions of dihydro-derivatives (from reduction of the cations with sodium borohydride or sodium dithionite) with electrophiles are investigated.Reactivity towards nucleophiles was studied to evaluate, (a) the regioselectivity of nucleophilic addition, and (b) the ease of decomposition of the resulting adducts into 4-substituted pyridines.

Synthetic Applications of N-N Linked Heterocycles. Part 8. Regiospecific Synthesis of 4-(α-Acylalkyl)pyridines by Attack of Lithium Enolates of Ketones γ to N-(2,6-Dimethyl-4-oxopyridin-1-yl)pyridinium Salts

The addition of N-(2,6-dimethyl-4-oxopyridin-1-yl)pyridinium salts (2) - (4) to lithium enolates (1) of ketones in tetrahydrofuran at low temperatures gives regiospecifically high yields of 1,4-dihydro-adducts (5) - (7).These are readily isolated and can be decomposed under free-radical conditions, also in high yield, to 4-(α-acylalkyl)pyridines (8) - (10).Unsymmetrical dialkyl ketones give a mixture of two isomeric products, the ratio depending upon reaction conditions and steric factors. αβ-Unsaturated ketones, however, give products resulting from reaction exclusively at the position α' to the carbonyl group.

Synthetic Applications of N-N Linked Heterocycles. Part 7. The Preparation of 4-Alkyl- and 4-Aryl-pyridines by Regiospecific Attack of Grignard Reagents γ to Quaternary Nitrogen in N-(2,6-Dimethyl-4-oxopyridin-1-yl)pyridinium Salts

N-(2,6-Dimethyl-4-oxopyridin-1-yl)pyridinium salts (4), new reagents for the regiospecific synthesis of 4-substituted pyridines, give moderate to high yields of 4-alkyl- and 4-aryl-pyridines (8) - (10) on reaction with Grignard reagents.The scope and limitations on the reaction, which proceeds via 1,4-dihydro-intermediates (5) - (7), are explored.No 2-substituted pyridines were detected.Some reactions with organolithium compounds are also described.