Synthesis and Host-Guest Chemistry of Chiral Spirobifluorene-Based Macrocycles Soluble in Basic Aqueous Solution.

Synthesis and host-guest chemistry of water-soluble (pH 12.5) chiral spirobifluorene-based macrocycles 2-[n] were carried out. Cationic guests, such as quaternary ammonium salts, were accommodated well in the hosts. Cp 2 Co + was especially strongly bound in 2-[4] ( K a of up to 3.0 × 10 5 M -1 ). Enantioselective recognition with (l)-carnitine was also achieved.