Abstract
The unexpected formation of 6-methyl-2-(2-methylpropenyl)cyclohex-2 enone (6) during a deprotecting reaction of 1,3-dioxane (5) via an interesting,carbonyl-ene reaction at room temperature with original aim to,obtain 4,8-dimethyl-5-oxonon-6-en-1-al (4) is reported. An alternative,route to aldehyde (4) is also presented.