Stabilization of Aldehydes as Propylene Glycol Acetals.

Propylene glycol (PG) acetals (substituted 1,3-dioxalans) of a few representative aldehydes are prepared according to standardized methods in yields of 80-90%. A comparative study of the regeneration of citral from the corresponding dimethyl and PG acetals under mild acidic conditions showed that, although the former readily decomposed to an extent of 85%, the latter formed a near 1:1 equilibrium mixture with the generated aldehyde.