A new binding motif in molecular clips: 1-D polymeric self-inclusion in a phenol complex of a bis(methoxyphenyl)glycoluril

Nolte's bis(o-xylylenyl)diphenylglycoluril molecular clips, in which the phenyls act as conformational 'locks' of the receptor site, have been modified with p-methoxy substituents on the phenyls. While this change does not have a major effect on the complexation of guests such as resorcinol (m-dihydroxybenzene) in chloroform solution, it allows for new binding geometries in the solid state. The crystal structure of new host 1,6:3,4-bis(1,2-xylylene)tetrahydro-3a,6a-bis(4-methoxyphenyl)-imidazo[4,5-d] imidazole-2,5(1H,3H)-dione (11) complexed with 4-phenylphenol (4-PP) has been determined as its toluene solvate [(11):2(4-PP):0.5(C₇H ₈)]. Molecules of 11 aggregate in 1-D chains through polymeric self-inclusion via C-Hπ(aromatic) interactions: 2-D sheets form via aryl stacking of the 1-D chains and the 3-D structure consists of alternating sheets of 11 in between which sheets of (4-PP):0.5(C₇H₈) reside.