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A new set of hybrid guest molecules bearing organic and inorganic residues have been studied for their recognition by cyclodextrins in aqueous solution. The guest molecules consist of nitroanilines linked through their amino group to the dodecahydrido-closo-dodecaborate cluster B12H122−, which serves as an anchor group. They show sizable affinity to cyclodextrins, and unexpected photophysical properties, with a very strong and low-energy charge-transfer band. The dodecaborate cluster increases the pKa of the anilines by 5.0 to 5.7 pH units, and the deprotonated forms of the o- and p-nitroaniline derivatives show strong charge transfer absorption bands in the visible part of the spectrum. [ABSTRACT FROM AUTHOR]

Substituted undecahydrido-closo-dodecaborates [B12H11NR2]2− have potential use in materials and drugs, but have presented a synthetic challenge. Microwave-assisted palladium-catalyzed amination of iodo-dodecaborate [B12H11I]2− allows mild and reproducible formation of B–N bonds with aromatic amines, HN-containing heteroaromatics, and amides. The reaction allows general access to amides, reproducible reactions to dodecaborate-substituted anilines, and, for the first time, the substitution of dodecaborate with HN-containing heterocycles. [ABSTRACT FROM AUTHOR]