ChemInform Abstract: Lactones. Part 22. Synthesis and Reduction of α‐Aminomethylene‐δ,δ‐diphenyl‐δ‐valerolactones.

Abstract

170ChemInform Abstract Consecutive reaction of the δ-lactone (I) with ethyl formate (IV)/sodium hydride and piperidine (V) leads to the formation of the 3-piperidinomethylenetetrahydro-2(2H)-pyranone (IIIb). Condensation of (I) and the γ-butyrolactone (VI) with tris(dimethylamino)methane (II) produces the 3-(dimethylaminomethylene)tetrahydropyranone (IIIa) and the 3-(dimethylaminomethylene)furanone (VII). Reduction of the compounds (III) and (VII) with NaCNBH3 gives the 3-methylenetetrahydropyranone (VIII) and the furanone (IX) respectively. Hydrogenation of (III) in the presence of PtO2 leads to the formation of the tetrahydropyranone (X), whereas the compounds (XI) and (XII) are obtained by hydrogenation of (IIIa) in the presence of Pd/C. The compound (IIIa) shows a weak parasympatholytic but no antihistaminic activity.