Synthesis of a new bisbinaphthyl macrocycle for enantioselective fluorescent recognition

Abstract

Condensation of the acyclic (S)-bisbinaphthyl dialdehdye (S)-7 with one equivalent of (R,R)-1,2-diphenylethylene diamine leads to the formation of a new bisbinaphthyl macrocycle, (S)-3. This compound is an analog of the previously reported bisbinaphthyl macrocycle (S)-1. Although (S)-3 only contains half of the functional groups of (S)-1, it still shows significant enantioselectivity in the fluorescent recognition of mandelic acid. An ef of up to four has been observed, which is much higher than the acyclic analog (S)-2. This study provides a better understanding of this class of chiral fluorophores.