INCLUSION COMPOUNDS OF ORGANIC AZOCHROMOPHORES IN THE CAVITIES OF METAL-ORGANIC FRAMEWORKS (Cr, Al)- MIL-101: SYNTHESIS AND PHOTOCHEMICAL STUDIES

Inclusion compounds of nitrogen-containing aromatic chromophores 4,4 '-bispyridylethylene (bpe) and 4,4 '-azopyridine (apy) in the cavities of mesoporous metal-organic frameworks Cr-MIL-101 and Al-MIL-101 are prepared and characterized by elemental analysis and nitrogen adsorption methods with a goal of finding approaches to the design of solid photochromic materials combining the benefits of photochromes in liquid solutions (high quantum yields) and in solid states (increased resistance to photodegradation). Photochemical properties of these compounds are qualitatively studied. Compound apy@Al-MIL-101 exhibits higher photoactivity than polycrystalline apy. Three other inclusion compounds are not photoactive. Possible reasons of the lack of photoactivity in these compounds are discussed.