(3)-Substd. (2,5)-dimethoxy-tetrahydrofuran intermediates prepn. - by a Wittig reaction between (2,5)-dimethoxy tetrahydrofuran-(3)-carbaldehyde and a phosphorylide

摘要

3-Substd. 2,5-dimethoxytetrahydrofurans of formula (I) are new, (where R1 is H or 1-4C alkyl, pref. Me or Et, R2 is H, Ph or opt. olefinically unsatd. 1-11C aliphatic, aliphatic-cycloaliphatic or cycloaliphatic gp. opt. contg. O in the form of an alkoxy, carbonyl, alkoxycarbonyl or acetal gp., or R1 and R2 together form an opt. alkyl-substd. 4-8C alkylene gp.). (I) are intermediates in the prepn. of the terpenoids dendrolasin and torreyal which are perfumes. Dendrosalin is also an insecticide effective against ants. Some (I) are themselves perfumes.