Stereochemistry of heterocycles - XXXIX. Stereochemistry of 2-methyl-5-alkyl-5-phenoxy-1.3-dioxanes

Abstract

2-Methyl-and 2,5-dialkyl-5-phenoxy-1,3-dioxanes were synthesized and separated into their geometrical isomers by precision rectification. The configuration and conformations of these isomers were determined by PMR spectroscopy. It is shown that the low-boiling trans isomers exist primarily in the chair conformation with an equatorial phenoxy group, whereas the high-boiling cis isomers exist primarily in the chair conformation with an axial phenoxy group. © 1976 Plenum Publishing Corporation.