The reaction of C 60 with Re 3 (µ-H) 3 (CO) 11 (NCMe) in refluxing chlorobenzene produces Re 3 (µ-H) 3 (CO) 9 (µ 3 -η 2 ,η 2 ,η 2 -C 60 ) (1) in 50% yield. Initial decarbonylation of 1 with Me 3 NO/ MeCN followed by reaction with PPh 3 in boiling chlorobenzene affords Re 3 (µ-H) 3 (CO) 8 (PPh 3 )-(µ 3 -η 2 ,η 2 ,η 2 -C 60 ) (2) in a low yield (26%). Treatment of 1 with PhCH 2 NdPPh 3 at room temperature gives a benzyl isocyanide substituted product Re 3 (µ-H) 3 (CO) 8 (CNCH 2 Ph)(µ 3η 2 ,η 2 ,η 2 -C 60 ) (3) in 53% yield. Compounds 1, 2, and 3 have been isolated as crystalline solids and characterized by spectroscopic (infrared, mass, 1 H, 31 P, and 13 C NMR) and analytical data. The structure of 3 has been determined by a single-crystal X-ray diffraction study. The C 60 ligand is coordinated to the trirhenium triangle in a µ 3 -η 2 ,η 2 ,η 2 bonding mode, and the benzyl isocyanide ligand occupies an axial position of a rhenium atom. Electrochemical properties of 1 and 2 have been studied by cyclic voltammetry (CV) in chlorobenzene (CB) solutions. The general features of CV curves have revealed four reversible redox couples for 1 and 2 in the CB potential window. The CV results suggest that a C 60 -mediated electron transfer to the trirhenium center takes place in 1 2species for 1 and 2 3for 2.

A chiral foldamer that consists of three indolocarbazoles and chiral amide residues folds into a helical conformation with the orientation bias, thus displaying characteristic CD signals. The X-ray crystal structure of its chloride complex was found to be a left-handed (M-) helix which stacks to give one-dimensional columnar arrays.

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Indolocarbazole-pyridine hybrid foldamers are strongly fluorescent in an extended random conformation, but the fluorescence is completely quenched upon folding to a helical conformation due to the compact stacking between aryl planes in the backbone. Anion binding disturbs the helical conformation, thus regenerating the fluorescence of the foldamers. This unique property has been utilized to develop a fluorescence turn-on probe for anions such as sulfate and fluoride.