Synthesis and Application of New Compounds with Both Axial and Helical Chiralities

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We succeeded in synthesizing 1,1'-bi-2-naphthol (BINOL) oligomers (dimer~octamer), which are directly connected at the 3,3'-positions of (R)-BINOL, in pure states and in good overall yields. The dimer was found to work as an excellent NMR shift reagent for chiral sulfoxides. The corresponding mono-calcium complex and low-valent dinuclear Ti-complex were found to work as a chiral bifunctional catalyst for the Michael reaction of nitromethane and to be effective for the pinacol coupling reaction, respectively, in which induced-fit-type reactions are anticipated. The trimer caused interestingly unique helical assembly of water molecules thus leading to the formation of chiral single strand water wire. It was found that the dynamic chirality of oligoBINOLs could be controlled by external stimuli such as pH. The UV-VIS and CD spectra of oligoBINOLs showed unusual trend on the pentamer indicating the formation of a unispiral structure.