56986-88-0Relevant academic research and scientific papers
A Three-Step Pyridoannelation of Carbonyl Compounds
Marchetti, Mauro
, p. 1761 - 1765 (2007/10/02)
The elaboration of a pyridine nucleus onto an α-methylene carbonyl compound can be accomplished through a three step reaction sequence based on the regiospecific alkylation of N,N-dimethylhydrazones with bromoethyl-1,3-dioxolane.Scope and limitations of the new method are considered.
Regioselective Addition of Grignard Reagents to 1-Acylpyridinium Salts. A Convenient Method for the Synthesis of 4-Alkyl(aryl)pyridines
Comins, Daniel L.,Abdullah, Abdul H.
, p. 4315 - 4319 (2007/10/02)
The addition of Grignard reagents to 1-acylpyridinium salts afforded 1-acyl-2-alkyl(aryl)-1,2-dihydropyridines and 1-acyl-4-alkyl(aryl)-1,4-dihydropyridines.The regioselectivity of this reaction, 1,2- vs. 1,4-addition, was examined and found to be dependent upon the structures of the Grignard reagent and the 1-acyl group.Pyridine, 2-picoline, and 3-picoline were studied, and in most cases, significant amounts of 1,4-addition occurred.When a catalytic amount of cuprous iodide was present, nearly exclusive 1,4-addition resulted.The crude 1,4-dihydropyridines were aromatized by heating with sulfur to provide 4-substituted pyridines and picolines in good yield and high isomeric purity.
