Halogen bonding: A powerful, emerging tool for constructing high-dimensional metal-containing supramolecular networks

Halogen bonding (XB), an attractive and valuable noncovalent interaction, has recently been exploited as an important tool in crystal engineering. The recent upsurge in crystal engineering has been prompted by the wide use of XB in the formation of liquid crystals and has implications for studies on non-linear optics (NLO), gels, anion recognition, magnetic and conducting materials, and porous and catalytic materials, among other topics. However, at present, most studies focus on XB-based organic supramolecular networks and do not consider metal-containing supramolecular networks. In this review, we provide an update on the recent advances in XB development to summarize the role of XB in the assembly of metal-containing supramolecular networks. We begin by introducing the reader to halogen-related interactions by highlighting a selection of typical organic supramolecular networks. Next, we present an overview of metal-containing supramolecular networks based on XB in metal halide/pseudohalide, metal 2,2'-dipyridylamino/s-triazine, metal quinolylsalicylaldimine, metal thiacalixarene, metal tetrathiafulvalenium (TIT), metal porphyrin, and metal iodo-benzenecarboxylic acid systems. The conclusions describe the potential applications of halogen-bonded supramolecular networks. A major goal of this review is to provide an organized and illustrative account of the recent work on XB-based, high-dimensional supramolecular networks, particularly metal-containing supramolecular networks. Finally, prospective directions for research involving XB in high-dimensional supramolecular architectures will be discussed. (C) 2015 Elsevier B.V. All rights reserved.