When recrystallized from an appropriate solvent, orthogonal bis(resorcino1)-anthracene compound l a as host forms molecular sheets involving an extensive hydrogen-bonded network. This generates supramolecular cavities which incorporate two molecules of recrystallization solvent such as ketones and esters as guests via host-guest hydrogen-bonding, The guest incorporation under competitive recrystallization conditions is highly selective; even a difference by one methylene group in the guests can be discriminated. The supramolecular cavities with included guest molecules are connected with each other, giving more or less continuous channels. Heating host-guest adducts in vacuo affords polycrystalline guest-free apohost. The apohost binds ketone and ester guests not only as liquids but also as gases and solids. The host:guest stoichiometry is 1:2 in most cases. Solid-state complexation using a 1:3 or 1:4 (host to guest) mixture affords 1:2 host-guest cocrystals and 1 or 2 equiv of unreacted guest simply remains as such. The adducts lw2(guest) thus obtained under solid-liquid, solid-gas, or solid-solid conditions exhibit essentially the same powder X-ray diffraction patterns as their authentic single crystals. Apohost la also binds hydrocarbons and haloalkanes such as benzene, p-xylene, and chloroform again in a 1:2 (host to guest) molar ratio. These results demonstrate that guest molecules can diffuse in the crystal lattices of apohost la. As compared with the conesponding recrystallization processes, guest-binding to preformed apohost is apparently far less selective with respect to the guests. This is due to a kinetic preference for smaller guests, even without a hydrogen-bonding site as in hydrocarbons, which are capable of more facile lattice diffusion. The sorption-desorption of liquid and gaseous guests can be repeated many times. The guest-binding properties of apohost l a is discussed from a viewpoint of a functional organic counterpart of porous inorganic crystal zeolites.

Anthracene−monoresorcinol derivative 1 forms hydrogen-bonded poly(resorcinol) 1D chains, which self-assemble via interpenetration or intercalation of the orthogonal anthracene (A) substituents. Guest-binding in the resulting cavities leads to either, depending on the guests (G, aromatic or aliphatic), an alternate ···A·G·A·G··· (monomeric) or an ···A·A·G·G··· (dimeric) lattice pattern. The monomeric lattices show a remarkable linear-alkyl vs branched-alkyl selectivity in the guest-binding. The dimeric lattices are characterized by their exclusive emission of excimer fluorescence. Self-assembly of the present 1D chains is thus functional and also flexible and dynamic; removal, addition, and exchange of guest molecules readily occur in the solid states.

The crystal structures of two adducts (1´2 H 2 O´2 IBB and 1´4 THF; IBB isobutyl benzoate) of an orthogonal porphyrin ± bisresorcinol derivative, the Zn II complex of 5,15-bis(3,5-dihydroxy-1-phenyl)octaethylporphyrin (1), are described. Both adducts contain an extensive hydrogen-bonding network, which forces the porphyrin rings into a columnar alignment. The resulting sheets are layered to give either a staggered arrangement (in adduct 12 H 2 O´2 IBB) or herringbone-type edge-to-face contacts (in adduct 14 THF) of the porphyrin moieties in neighboring sheets. In the large cavities left, guest molecules are incorporated by hydrogen bonding (resorcinol´´´OH 2´´Í BB) in adduct 1´2 H 2 O´2 IBB, or by a combination of hydrogen bonding (resorcinol´´´THF) and metal coordination (Zn II´´´T HF) in adduct 1´4 THF. The use of the large porphyrin spacer in the orthogonality strategy is discussed in the light of the known crystal structures of related anthracene ± bisresorcinol derivatives.

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