Figure 6
(a) The structure of compound 9, including selected bond lengths (in Ångstroms; given as one less significant figure than in the CIF for clarity), as determined by X-ray analysis, and (in brackets) via geometry optimization in vacuo at the B3LYP/6-311G(d,p) level of theory. (b) Stereoscopic view of the structure of compound 9, as determined by X-ray diffraction. (c) Two views of the octaazacyclodecane backbone of compound 9, in which atoms other than those that define the ring have been hidden from view (N atoms blue and C atoms gray). Viewpoint I is from the top of the ring system. Viewpoint II is from the side, where the two C atoms within the ring system are eclipsed. Displacement ellipsoid plots are provided in the supporting information. |