92082-39-8Relevant academic research and scientific papers
Highly Regioselective Phosphine-Promoted [2+2+2] Annulations of Cyanoacetylenes and N -Tosylimines to 1,2-Dihydropyridine-3,5-dicarbonitrile Derivatives
Zhang, Jinfeng,Zhang, Qi,Ji, Xin,Meng, Ling-Guo
, p. 1095 - 1099 (2019)
A series of fully functionalized dihydropyridine-3,5-dicarbonitrile derivatives were easily prepared through [2+2+2] annulations of cyanoacetylenes and N -tosylimines in the presence of tertiary phosphine. The scope of the cyclization reaction was investi
Pyridine Syntheses. II. Condensation Routes Toward Streptonigrin Ring C [1]
Robinson, J. Michael,Ahmed, Masood,Alaniz, Nicky J.,Boyles, Timothy P.,Brasher, Chris D.,Floyd, Kimberly A.,Holland, Preston L.,Maruffo, Laura D.,McMahan, Terry L.,Middleton, Stan,O'Hara, Kevin D.,Pack, Marcia J.,Reynolds, Brandon D.,Rodriquez, Romelia R.,Sawyer, Dennis E.,Sharp, Elena,Simpson, Sharai L.,Vanlandingham, Clint L.,Velasquez, Rebecca S.,Welch, Brian M.,Wright, C. David
, p. 65 - 69 (2007/10/03)
Alternative complimentary syntheses of penta-substituted pyridine rings with full regiochemical control of substituents were studied as a method for the synthesis of Streptonigrin (1). Various α-substituted acetophenones 2 were reacted with enones 3 in acetic acid/ammonium acetate and air to afford penta-substituted pyridines 4. α-Substituents that could provide a source of exocyclic nitrogen at position 3 of these Steptonigrin ring-C models proved to be the limiting factor. However, an inverse "3+2+1" cyclocondensation of α-cyanochalcone 5c with 2-furyl ethyl ketone (6b) afforded the desired model 6-(2-furyl)-5-methyl-2,4-diphenyl-3-pyridinecarbonitrile (4g) in 75% yield.
SYNTHESIS OF 3,5-DICYANO-4-PHENYL-2,6-BIS(4-p-TERPHENYLYL)-1,4-DIHYDROPYRIDINE. AN ATTEMPT AT EXTENDING THE HANTZSCH SYNTHESIS
Marchalin, Stefan,Kuthan, Josef
, p. 1962 - 1970 (2007/10/02)
The 3-oxopropanenitrile IIIc, prepared from 4-acetyl-p-terphenyl (IV) by the sequence IV -> V -> VI -> IIIc, reacts with benzaldehyde and ammonium acetate in acetic acid to give the Hantzsch dihydropyridine VIIc and the corresponding pyridine derivative VIIIc.The alternative cyclocondensation of benzylidene derivative IIc and 3-oxopropanenitrile IIIc in the presence of ammonium acetate exclusively gives the pyridine derivative VIIIc.Rate of thermal and oxidative aromatizations of the 1,4-dihydropyridine derivatives, VIIa-VIIc -> VIIIa-VIIIc, decreases in the order VIIc > VIIb > VIIa.Mechanism of these transformations and spectral characteristics of compounds VIIc and VIIIc are discussed with regard to their molecular structure.
