Abstract
A synthetic application of the rate difference in oxidation of regioisomerically substituted N -acyldihydropyridines is reported. This has allowed for isolation of pure 4-substituted pyridine isomers without the need for chromatography. Diels-Alder adducts between a dihydropyridine and DDQ were isolated and formation of novel hydroquinone ethers was also observed during some reactions.
Key words
N -acyldihydropyridine - DDQ oxidation - Diels-Alder - hydroquinone ether
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