ИСТИНА

We proposed and developed a novel methodology for the synthesis of functionalized derivatives of 1-aza-2,3-benzoazacrown ethers by a stepwise transformation of the macrocycle of benzocrown ethers. The spatial structures and complexing properties of the starting benzocrown ethers, target benzoazacrown ethers and their closest structural analogues were comprehensively studied. It was established that the derivatives of N-alkylbenzoazacrown ethers have a much higher ability to bind metal and ammonium cations in comparison with the corresponding N-phenylazacrown ethers. In the complexation properties they are comparable with benzocrown ethers and, in certain cases, surpass them. The first reason is a high extent of preorganization of a macrocycle of N-alkylbenzoazacrown ethers for complex formation with cations. And the second reason is a higher electron-donating ability of the macrocyclic nitrogen atom. A new approach to the synthesis of dinitrodibenzodiazacrown ethers is proposed. It is based on one-stage transformation of the macrocycle of the cis-isomer of dinitrodibenzo-18-crown-6 ether by the action of aliphatic diamines. The synthesis of the styryl dyes containing an N-methylbenzoazacrown-ether fragment was elaborated. Detailed studies by electronic spectroscopy, NMR and X-ray diffraction revealed a great potential of these dyes for use as optical molecular sensors for alkali and alkaline earth metal cations. This work was supported by the Russian Foundation for Basic Research, and the Russian Academy of Sciences.