Leaf Alcohol

Part XVIII. Condensation of Leaf Aldehyde by Means of Diethylamine

抄録

The diethylamine-catalyzed aldol condensation of E-2-hexenal yielded a mixture of 2-E, 4-E, 6-E- (IV-a) and 2-E, 4-Z, 6-E-4-ethyldeca-2, 4, 6-triene-1-al (IV-b). Structual and geometrical elucidation of both alcohols were made by means of spectral evidence as well as by the catalytic hydrogenation leading to the same 4-ethyldecanol (VI). The “b-peak substance” detected in the leaf alcohol reaction products was proved to be identical with 4-ethyldecanol (VI). The treatment of the trienal containing the central Z-double bond with sodium under the leaf alcohol reaction condition failed to afford ethyl-propyl-benzyl alcohol, but gave 4-ethyldecanol (VI). This result safely excludes the operation of the previously suspected valence tautomerism (Cope rearrangement) in the leaf alcohol reaction, and accounts for the pathway of the formation of (VI).