A highly nucleophilic vinylation reagent, lithium vinyldimethylmagnesate (vinylMe2MgLi), is obtained by mixing vinylmagnesium chloride (1 equiv.) and MeLi (in diethoxymethane; 2 equiv.). The application of this new reagent in the completely regioselective synthesis of 6‐vinyl‐3,6‐dihydro‐1H‐pyridin‐2(1H)‐ones by simple 1,6‐additions to 2‐pyridones is described. Examination of the scope and limitations of the addition revealed the influence on the efficiency of the 6‐vinylation reaction of substituents on the nitrogen atom and on the 2‐pyridone ring.
Regioselective Synthesis of 6-Vinyl-3,6-dihydropyridine-2(1H)-ones Through Simple Addition of a Vinylmagnesium "Ate" Complex to 2-Pyridones. -Lithium vinyldimethylmagnesate can be formed directly by mixing of vinylMgCl and MeLi. The vinyl "ate" complex, although less nucleophilic than allylmagnesate, is capable of regioselective addition to N-substituted 2-pyridones. The presence of substituents on the 2-pyridone ring like 3-Cl, 3-Ph, and 3-PhS enhances the reactivity of the 2-pyridone towards the addition reaction, overcoming the undesired basic properties of the vinyl magnesate, and thus improving the yields of the vinyldihydropyridinone addition products. -(SOSNICKI*, J. G.; DZITKOWSKI, P.; STRUK, L.; Eur. J. Org. Chem. 2015, 23, 5189-5198, http://dx.doi.org/10.1002/ejoc.201500605 ; Inst. Chem. Environ. Protect., West Pomeranian Univ. Technol., PL-71-065 Szczecin, Pol.; Eng.) -H. Hoennerscheid 51-148
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