1.3-Diazanes. conformational studies

Several groups (65, 71-75) have studied the 1,3-diazane system J06 (R=R =H and/or CHg) and found that these compounds exist as a mixture of conformers 107 and 108. In these studies, the conformation 109 with two anomeric effects was not considered. It is conceivable that when R=R =H, the most stable conformation is 109 rather than 108. Also, when R=CH3 and R =H, conformer 109 with its second anomeric effect to compensate for the steric effect caused by the axial N-rnethyl group could compete with conformer 108 which... 

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