Synthesis,nuclear magnetic resonance,and X-ray structural investigations of 1,6-diaza-9,12-dioxacyclotetradeca-2,5-dione

The molecular structure of l,6-diaza-9,12-dioxacyclotetradeca-2,5-dione has been investigated by X-ray and NMR methods. The crystals are monoclinic:C2/c,Z=4,a=8.5571(3),b=14.468(1),c=10.092(2) Å,=113.38(1)°. The structure was solved by direct methods, and refined toR=0.051 on 1082 unique reflections. The molecule exhibits a crystallographic twofold symmetry axis, the axis bisecting the 3C-4C and 10C-11C bonds, which is in full agreement with NMR findings.