THE RELATIVE EASE OF REDUCTIVE CLEAVAGE OF 1,3-DIOXOLANES AND 1,3-DIOXANES IN ETHER SOLUTION BY LiAlH4–AlCl3

Abstract
In ether solution, 1,3-dioxolanes are hydrogenolyzed faster by LiAlH4–AlCl3 than are the corresponding 1,3-dioxanes. This difference is attributed to the relative ease of oxocarbonium ion formation in the rate-determining step of the reaction. The results obtained have been utilized to explain the selective cleavage of the five- and six-membered acetal structures found in the polyacetals of hexitols.