STRUCTURE AND CONFORMATION OF HETEROCYCLES. 13. CONFORMATIONAL ANALYSIS OF 2,3-DI(R)OXY-1,4-DIOXANES: ANOMERIC AND GAUCHE EFFECTS

Article abstract of DOI:10.1016/S0040-4020(01)88441-6

A series of trans- and cis-2,3-di(R)oxy-1,4-dioxanes (R = Me,Ph,Ac) and some 2,5-disubstituted analogs were prepared and analysed by various NMR techniques.The trans isomers occur in more than 96percent as diaxial conformers.Molecular mechanics calculations largely confirm these findings, which are interpreted in terms of combined anomeric and gauche effects.