Synthesis of 2-ethoxy-2-carbethoxy-δ5 -dihydropyrans and their derivatives
Acrolein and methyl vinyl ketone undergo diene condensation with ethyl α-ethoxyacrylate to give the corresponding 2-ethoxy-2-carbethoxy-Δ5-dihydropyrans in 50–60% yields. The reduction of the latter with lithium aluminum hydride gave the hydroxymethyl derivatives of dihydropyrans, while ammonolysis gave amides of 2-ethoxy-Δ5-dihydropyran-2-carboxylic acids.
KeywordsAluminum Methyl Ethyl Lithium Organic Chemistry
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