Chiral Cryptates Derived from a Hexaazamacrocycle
journal contributionposted on 18.05.2018, 00:00 by Aleksandra Gerus, Katarzyna Ślepokura, Jarosław Panek, Aleksandra Turek, Jerzy Lisowski
The reactions of hexaazamacrocycle 1 with 2,6-bis(bromomethyl)pyridine or 2,6-bis[(tosyloxy)methyl)]pyridine in the presence of appropriate carbonates result in the formation of derivatives of cryptand 6: enantiopure azacryptates of sodium and potassium. Crystal structures of these compounds indicate interaction of a metal ion with four pyridine nitrogen atoms and four tertiary amine atoms. The competition reactions monitored by NMR spectroscopy indicate preferential binding of Na+ over K+ as well as higher affinity of 6 for Na+ in comparison with the [2.2.1] cryptand.