Synthesis of 2,3,5,6-Tetrasubstituted Pyridines from Enamines Derived from N,N-Dimethylformamide Dimethyl Acetal
                                
                                    
                                        作者:Fathi A. Abu-Shanab、Alan D. Redhouse、J. Robin Thompson、Basil J. Wakefield                                    
                                    
                                        DOI:10.1055/s-1995-3954
                                    
                                    
                                        日期:1995.5
                                    
                                    Reactions of 1,3-dicarbonyl compounds with N,N-dimethylformamide dimethyl acetal, followed by cyanothioacetamide or cyanoacetamide and sodium hydride, then acidification, give 5,6-disubstituted 3-cyanopyridine-2(1H)-thiones or 5,6-disubstituted 3-cyanopyridin-2(1H)-ones 4. Analogous reactions with the malono-nitrile dimer give 5,6-disubstituted 3-cyano-2-(dicyanomethylene)-1,2-dihydropyridines 9.
                                    1,3-二羰基化合物与
N,N-二甲基甲酰胺二甲基
缩醛反应,再与
氰基
硫代乙酰胺或
氰基乙酰胺与氢化
钠反应,然后酸化,得到5,6-二取代的3-
氰基吡啶-2(1H)-
硫酮或5,6-二取代的 3-
氰基吡啶-2(1H)-酮 4. 与
丙二腈二聚体进行类似反应,得到 5,6-二取代的 3-
氰基-2-(二
氰基亚甲基)-1,2-
二氢吡啶 9。