Anthracene Based Bulky Diol Hosts. Crystal Structures of a Free Host and of Inclusion Compounds with Dipolar Guests

Crystalline inclusion compounds of a new diol host featuring a combination of anthracene and 9-fluorenol units

“…Nevertheless, a comparative examination of the inclusion structures of the 1:2 complexes of 1 and 2 with DMSO as guest component reveals that the OH groups of 2 take part in host -host strand formation with a lateral attachment of guest molecules showing different modes of host -guest interactions. In contrast, the crystal structure of the corresponding complex of 1 is composed of discrete OZH· · ·O bonded host -guest associates where each of the host hydroxyl groups binds to a guest oxygen atom (11). These aggregates are further connected by weaker intermolecular interactions.…”

“…Anthracene moieties with different substitution patterns, especially the 9,10-anthrylene segment that gives rise to a linear structure, have also been used (6,10). A particular host compound of this type bearing two bulky 9-hydroxy-9-fluorenyl residues linked by a 9,10-diethynylene elongated anthracene spacer (1) (Scheme 1) as well as its clathrate behaviour has been recently reported (11,12). A change in the molecular bulk should result from the direct attachment of the 9-hydroxy-9-fluorenyl moieties to the 9,10-anthrylene spacer unit as in the title compound 2 (Scheme 1).…”

Host compounds based on the rigid 9,10-dihydro-9,10-ethanoanthracene framework: selectivity behaviour in mixed isomeric dichlorobenzenes

“…7b (the reason for the ALERT level B in the checkcif report is that the two hydroxyl groups in H2 do not form H-bonds with single acceptor atoms, but instead engage in these intramolecular O-H⋯π interactions with the phenyl groups of the anthracene unit). Since no strong host intramolecular hydrogen bonding interactions were evident in this complex, this host molecular geometry is referred to as the "inactive" form of H2, as defined by Csöregh et al [37][38][39] As was the case in 3(H2)•o-Xy from a previous investigation, 35 the m-DCB guest species in 3(H2)•m-DCB were surrounded by four molecules of H2 creating host-guest motifs that stretched out along the c-axis, forming tunnel voids in which the guests were housed. Fig.…”

“…As in H2•o-DCB, in the 3(H2)•m-DCB complex was also identified an intramolecular host⋯host π⋯π contact (3.572(2) Å, slippage 1.537 Å) and two intramolecular O-H⋯π 9), this being, once more, the "inactive" form of H2, since no strong intramolecular host O-H⋯O interactions could be identified in this complex. [37][38][39] Guest retention was accomplished through host⋯guest C-H⋯Cl The host molecule in H3•m-DCB also assumed the "inactive" form [37][38][39] Guest retention was accomplished through a single C-Cl⋯π interaction (3.864(2) Å, 134.2(1)°) between the chlorine atom of the guest molecule and the anthracene aromatic ring (Fig. 14).…”