Figure 1.

(a) Space-filling representation of hexamer 9, of mixed macrocycle 5, viewed along the 3bar axis of the capsule. The six diethyl ether molecules bound to the hydrogen bond donors oriented toward the interior of the capsule are shown in blue; the six diethyl ether molecules bound to hydrogen bond donors oriented toward the exterior of the capsule are shown in orange. Host oxygen atoms are given in red. (b) Capsule 9 viewed perpendicular to the 3bar axis. Three of the six hydrogen bond donors that are not involved in the O—H⋅⋅⋅O hydrogen bonding scheme are indicated by the white arrows. The remaining three are rotated by 60^o and hidden from view on the bottom half of a.