High dilution reactions between a diamine and a diacid activated with 1,3-thiazolidine-2-thione afforded bicyclic polyamines after reduction of the amido moieties with borane. The cyclisation yields ranged between 34 and 84% and presumably depend on the rigidity of the reagents. Selection of the most appropriate procedures for the deprotection of tosylated amino groups and for the addition of carboxylic groups appear to depend on the structure and the cavity size of the macrocycles. For instance, encapsulation of a Na+ ion as seen by 23Na NMR prevents the substitution of the secondary amino groups of the polyaza ligands by acetate functions.
高稀释反应中,二胺与通过
1,3-噻唑烷-2-酮活化的二酸反应,经过
硼烷还原酰胺基团后,获得了 bicyclic 聚胺。环化产率在34%到84%之间,可能依赖于试剂的刚性。选择最合适的去保护托烯基
氨基团和加入羧基的程序,似乎取决于大环的结构和腔体大小。例如,Na+离子的封闭,如23Na NMR所示,阻止了聚氮
配体的次
氨基团被
醋酸基团取代。