Binding of Ammonium Cations by Three-Dimensional Hosts

2 Binding of Ammonium Cations by Three-Dimensional Hosts 

Ammonium cations may also be bound by cation- r interactions by large cyclophanes such as 3.102 (calixarene-derivatives - see Section 3.14). The rigid, deep-cavity tetrahydroxy receptor 3.102a is able to selectively bind tetramethylammonium ions with X 10 M in chloroform solution. 

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