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A methodology for the synthesis of substituted pyridines via Diels-Alder condensation of N-(O-tbutyldimethylsilyloxy)-3-methyl-l-aza-1,3-butadiene (65) and N-(O-tbutyl dimethylsilyloxy)-2-methyl-l-aza-1,3-butadiene (66) with substituted 1,4-benzoquinones was developed.The novel azadienes 65 and 66 were synthesized by direct condensation of N-(Otbutyldimethylsilyloxy) hydroxylamine with methacrolein and methyl vinyl ketone respectively. The azadiene 66 was also prepared by condensation of N-(O-tbutyldimethylsilyloxy) hydroxylamine with 3-bromo-2-butanone followed by dehydrohalogenation of the resulting imine with potassium tbutoxide.The Diels-Alder condensation of 66 with N-phenylmaleimide produced N-phenyl-6methyl-2,3-pyridinedicarboximide (82). The [4+2] cycloaddition of 66 with Nphenylmaleimide, naphthoquinone, 2-acetamido-5-bromo- a...