| Abstract
| - Two families of molecular frameworks which grow as homochiral single crystals are described.Both consist of multiple interpenetration of the three-connected chiral (10,3)-a (Y*) network and result fromthe tridentate coordination of the 1,3,5-benzenetricarboxylate (btc) ligand to octahedral metal centers whichact as linear connectors. The nature of the interpenetration is controlled by the auxiliary ligands bound in theequatorial plane of the metal center. Ethylene glycol (eg) binds in a unidentate fashion to form phase A whichhas 28% accessible solvent volume and contains four interpenetrating (10,3)-a networks. 1,2-Propanediol (1,2-pd) coordinates as a bidentate ligand to yield a phase B with a greatly enhanced 51% of solvent accessiblevolume, because only two (distorted) (10,3)-a‘ networks interpenetrate. Ligands in the void space and boundto the metal center can both be liberated thermally: the kinetics of this process allow isolation of microporousdesolvated crystalline A and B. The porous phases lose crystallinity reversibly upon further loss of ligandsbound to the equatorial metal: crystallinity is restored upon exposure to the vapors of simple alcohols, whichcan also effect conversion of B to A. Both phases present interpenetrating network topologies that are uniqueto chemistry and adopt space groups that are new for molecular solids: A crystallizes in P4232 and B adoptsI4132. B can be grown homochirally from enantiomerically pure diol template. The stereochemistry of thealcohol bound to the metal controls the helicity of the chiral framework. The structure determination of the1,2-propanediol phase represents the first demonstration that chiral molecules can specifically template helixhandedness in a chiral porous framework solid.
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