The inherent instability of 1,3-dioxan and the conformation of 1,3,7,9-tetraoxacyclododecane
Abstract
The conformation of 1,3,7,9-tetraoxacyclo-dodecane, formed by dimerization of 1,3-dioxan, is shown by n.m.r. spectroscopy to be ‘square,’ with both 1,3-dioxa-groupings across corners, and to possess a very high conformational barrier (11 kcal/mol).