Y. Nagawa et al., Intramolecular sp(2)-CH center dot center dot center dot O interaction in the single crystal of macrocyclic polyethers with an isobutenyl group, CHEM LETT, (9), 2000, pp. 1096-1097
Effects of the ring size on the conformation in the macrocyclic polyethers
with an isobutenyl group have been studied by X-ray crystallography: the in
tramolecular CH ... O interaction has been observed in the compound having
22 membered macrocyclic ring.