Abstract
1,3-Dioxolanation of αβ-unsaturated aldehydes with 1,2-bis((trimethylsilyl)oxy)ethane in the presence of trimethylsilyl trifluoromethanesulfonate as catalyst has been systematically investigated. These silylated reagents readily acetalize aliphatic, highly conjugated aliphatic, and aromatic enals. Under the mild, aprotic conditions of the reaction, olefins do not rearrange or isomerize, and the acid-sensitive propionyloxy, (tetrahydropyranyl)oxy, and vinyl ether moieties are relatively stable. Aromatic bromide, furan, thiophene, and nitro functionalities are also inert. The only limitation found is in the case of 4-(dimethylamino)cinnamaldehyde, which did not afford a detectable amount of the corresponding dioxolane. © 1987 American Chemical Society.