Enantioselective fluorescent recognition of chiral acids by 3- and 3,3 '-aminomethyl substituted BINOLs

摘要

Benzylaminomethyl groups are introduced to the 3,3'-positions of BINOL. The resulting compounds can be used to conduct the enantioselective fluorescent recognition of mandelic acid and N-benzyloxycarbonylphenylglycine. ln the presence of (S)-mandelic acid, compound (R)-2 showed over 30-fold fluorescence enhancement with the ef [ef=enantiomeric fluorescence difference ratio=(I-s-I-0)/(I-R-I-0)] up to 4.2. In the presence of D-N- benzyloxycarbonylphenylglycine, compound (RR)-4 showed up to 15-fold fluorescence enhancement with the ef up to 5.0. These high fluorescence sensitivity and enantioselectivity make compounds (R)-2 and (RR)-4 practically useful sensors for the recognition of the chiral acids in apolar solvents. (C) 2004 Elsevier Ltd. All rights reserved.