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Indexed by:期刊论文

Date of Publication:2008-01-01

Journal:CRYSTENGCOMM

Included Journals:SCIE

Volume:10

Issue:6

Page Number:759-764

ISSN No.:1466-8033

Abstract:The assembly of racemic molecular clips SS-and RR-1,1'-bis(1-(1,2,4-triazol-1-yl)ethyl)ferrocene (FcTz) into coordination polymers has been studied systematically. Stereoselective homochiral association of Zn(CH3COO)(2)center dot 4 H2O leads to the formation of one-dimensional helical chains having a right handed enantiomer 1 and a left-handed enantiomer 1' via self-assembly. The CD spectra of crystals of 1 and 1' exhibit the opposite Cotton responses and suggest that two enantiomers of the molecular clips are resolved by the metal-induced crystallization. On the other hand, the meso type association of CdI2 results in the formation of centro-symmetric two-dimensional sheets. It is shown that the product of the homochiral association is predominately formed when the metal center is tetrahedrally coordinated, and that of the meso-association is generated at the time the metal centers is sited in a mirror symmetric tetragonal pyramidal geometry. The weak but significant intermolecular interactions are also found to be essential in controlling the homochiral aggregation of these helical polymers and achiral sheets.