Two-Step Synthesis of (Z)-2-[2-Oxo-2,3-dihydropyrido[2,3-d]pyrimidin-4(1H)-ylidene]acetamide Derivatives from 2-Chloro-6-methylpyridine-3-carbonitrile

Abstract

(Z)-2-[1-Aryl-7-methyl-2-oxo-2,3-dihydropyrido[2,3-d]pyrimidin-4(1H)-ylidene]acetamides were prepared using a two-step sequence. The first step was the addition of magnesium enol­ates of tertiary acetamides to 2-chloro-6-methylpyridine-3-carbo­nitrile to give vinylogous urea derivatives, (Z)-3-amino-3-(2-chloro-6-methylpyridin-3-yl)propenamides. In the second step, these were reacted with aryl isocyanates in the presence of sodium hydride to give the corresponding pyrido[2,3-d]pyrimidin-2(1H)-one derivatives.

Key words

isocyanate - magnesium amide - magnesium enolate - pyridinecarbonitrile - pyridopyrimidine

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