New boron macrocycles based on self-assembly of Schiff bases

In order to investigate the formation of macrocyclic boronates, we carried out the reaction of 3-aminophenyl boronic acid with salicylaldehyde, 2-hydroxyacetophenone and 2-hydroxybenzophenone. In all cases, macrocyclic structures were formed and the X-ray crystallographic study of the trimeric complex derived from 2-hydroxyacetophenone showed that the macrocyclic system is asymmetric. (C) 2001 Published by Elsevier Science B.V. All rights reserved.