摘要:
IntroductionCrystal structures possessing the tetrahedral connectivity of diamond are described as diamondoid, and occur as two types, nonmolecular and supramolecular. In the nonmolecular structure type there are strongly bonding connectors between tetrahedral sites — often ditopic ligands binding tetrahedrally coordinated metal atoms1–3— and thus threedimensionally extended coordination networks. In contrast, in the supramolecular structure type there are identifiable molecules and weak intermolecular interactions. Supramolecular diamondoid lattices, less numerous than nonmolecular diamondoid lattices, are known mainly with hydrogen bond linkages. The tetrahedral molecules methane tetracarboxylic acid and adamantane1,3,5,7tetracarboxylic acid use the classic carboxylate hydrogen bonded pair as the intermolecular connector:4other tetrahedral molecules use pyridone arms for hydrogen bonding.4,5The cubanoid cluster (μ3-OH)4M4(CO)12forms diamondoid nets by hydrogen bonding involving the OH groups and additional ditopic linker molecules, including diamines and arenes (which form OH⋯arene⋯HO hydrogen bonds).61,3,5,7Tetraiodoadamantane forms a diamondoid net maintained by I⋯I intermolecular interactions.7Both classes of diamondoid structure commonly occur as interpentrating nonconnected nets.8This is because diamond lattices are comprised of fused adamantanoid cages, and the adamantanoid cage is characterised by a large central space relative to the edge length. Guest inclusion is an alternative mechanism for filling this space in diamondoid lattices. An example of the combination of interpenetrating diamondoid lattices held together by hydrogen bonding, and guest inclusion, is exhibited in the lattice formed by 2,7dimethyltricyclo[4.3.1.13,8]undecanesyn2,syn7diol with guests such as benzene, acetonitrile or dichloromethane.9
ISSN:1466-8033
DOI:10.1039/b100400j
出版商:RSC
年代:2001
数据来源: RSC