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Spectroscopic and Thermal Characterization of the Host-Guest Interactions between ?-, ?-, and ?-cyclodextrins and vanadocene dichloride.

ABSTRACT: Host-guest interactions between ?-, ?-, and ?-cyclodextrins and vanadocene dichloride (Cp(2)VCl(2)) have been investigated by a combination of thermogravimetric analysis, differential scanning calorimeters, PXRD and solid state and solution EPR spectroscopy. The solid state results demonstrated that only ?- and ?-cyclodextrins form 1:1 inclusion complexes, while ?-cyclodextrin does not form an inclusion complex with Cp(2)VCl(2). The ?- and ?-CD-Cp(2)VCl(2) inclusion complexes exhibited anisotropic electron-(51)V (I = 7/2) hyperfine coupling constants whereas the ?-CD- Cp(2)VCl(2) system showed only an asymmetric peak with no anisotropic hyperfine constant. On the other hand, solution EPR spectroscopy showed that ?-CD may be involved in weak host-guest interactions in equilibrium with free vanadocene species.

SUBMITTER: Morales A

PROVIDER: S-EPMC2770188 | biostudies-literature | 2008 Jun

REPOSITORIES: biostudies-literature

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Spectroscopic and Thermal Characterization of the Host-Guest Interactions between α-, β-, and γ-cyclodextrins and vanadocene dichloride.

Morales Alexis A Weber Ralph T RT Melendez Enrique E

Applied organometallic chemistry 20080601 8

Host-guest interactions between α-, β-, and γ-cyclodextrins and vanadocene dichloride (Cp(2)VCl(2)) have been investigated by a combination of thermogravimetric analysis, differential scanning calorimeters, PXRD and solid state and solution EPR spectroscopy. The solid state results demonstrated that only β- and γ-cyclodextrins form 1:1 inclusion complexes, while α-cyclodextrin does not form an inclusion complex with Cp(2)VCl(2). The β- and γ-CD-Cp(2)VCl(2) inclusion complexes exhibited anisotrop ...[more]

PMID: 19881887

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