Synlett 2006(15): 2364-2374  
DOI: 10.1055/s-2006-951469
ACCOUNT
© Georg Thieme Verlag Stuttgart · New York

Organic Ammonium Carboxylates as Supramolecular Building Blocks: The Role of Ionic Hydrogen Bonding

Kazuki Sada*, Takahiro Tani, Seiji Shinkai
Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
Fax: +81(92)8022821; e-Mail: sadatcm@mbox.nc.kyushu-u.ac.jp;
Further Information

Publication History

Received 30 November 2005
Publication Date:
08 September 2006 (online)

Abstract

Ion pairs and higher order aggregates of organic ammonium carboxylates have been recognized as important tools in supramolecular chemistry. The structures of these species are attributed to isotropic electrostatic interaction and hydrogen bonds between oppositely charged ions. This account describes the role of hydrogen bonding in the crystal structures of various organic ­ammonium carboxylates. The utility of these salts in the design of supramolecular assemblies such as organogels and higher order clusters in non-polar solutions is also demonstrated.

1 Introduction

2 Hydrogen-Bonding Ability of Organic Ammonium Carboxylate Salts

3 Hydrogen-Bond Networks in the Crystalline State

3.1 Quaternary Ammonium Salts

3.2 Tertiary Ammonium Salts

3.3 Secondary Ammonium Salts

3.4 Primary Ammonium Salts

3.5 Hydrogen-Bonding Properties of Ammonium Carboxylates

4 Organogelators Based on Organic Ammonium Salts

5 Cluster Formation of Ion Pairs in Non-Polar Solution

6 Implications for Surface Lys Salt Bridges in Proteins

7 Concluding Remarks