Well-defined Ion-pair Clusters of Alkyl- and Dialkylammonium Salts of a Sterically-hindered Carboxylic Acid. Implication for Hydrogen-bonded Lys Salt Bridges

Ion-pair clusters of simple alkylammonium carboxylates in solution and in the crystalline state were described as a model of Lys salt bridge. tert-Butylammonium triphenylacetate gives a well-defined tetrameric cluster by a cubic hydrogen bond (Hbond) network, and diisopropylammonium triphenylacetate gives a dimeric cluster by a cyclic network.