Heterobinuclear calixarene-based metal complexes for photo- and electrochromic molecular scale devices

• Applicant: Dr. Margit Gruner
• Subject Area: Organic Molecular Chemistry - Synthesis and Characterisation
• Term: from 2007 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 34631931

The project is directed to the design, synthesis, structural and physico-chemical investigation of calixarene derivatives and their metal complexes for new molecular devices. Photo- and voltage-driven molecular devices will be developed, wherein the photo- and electro active species are separated by a calixarene platform. It is planned to synthesize calixarene derivatives with functional groups both on the upper and lower rims for the binding of two active species which are able to perform electron (energy) transfer processes and to investigate their configuration and conformation as well as their dynamic host-guest behaviour using modern methods of gradient 1D and 2D nuclear magnetic resonance (NMR). Transition metal ions are envisaged as photo- and electro-active species. The project is based on an exploitation of both rims of the calixarene matrix for inner- and an outer-sphere coordination of c/(/)-metal ions and their complexes. The outersphere coordination of metal complexes will be achieved by cooperative electrostatic and Van der Waals interactions between metal complexes and positively (negatively) charged rims of the calixarenes. The inner-sphere coordination will be governed by the modification of the lower rim of calixarenes with CN, OH, NH2, COOH moieties. In the course of the project it is intended to synthesize metat-calixarene-metal molecular systems with various lengths of the calixarene bridge and to investigate the influence of the metal to metal distance on the electron (energy) transfer between the metal ion centres. Both kinetic measurements and structural and dynamic NMR investigations will be applied for these purposes. The elongation of the calixarene matrix will be realized by variation of the lower rim substituents.

• DFG Programme: Research Grants
• International Connection: Russia
• Participating Persons: Dr. Ingmar Bauer; Dr. Wolf Dieter Habicher; Professor Dr. Alexander Konovalov