摘要:
IntroductionThe cucurbit[n]urils are cyclic methylene-linked glycoluril oligomers of the type1, here abbreviated Qn. They possess a characteristic annular shape, with two carbonyl-fringed portals.1–3Recent research with the most common cucurbituril, Q6, has demonstrated that the guests xenon,4water,5THF,6–8toluene,9and pyridinium10andpxylylenediammonium5ions can be accommodated within the cyclic host, and that alkyl diamines threaded through the Q63,11and functionalised can provide the basis for the generation of rotaxane structures.12–16Metal ions1,5–8,17,18and metal clusters10,19,20are known to bind outside cucurbiturilsviacoordination or hydrogen bonding at the carbonyl groups, and a recent paper has described tetraazamacrocycles and their metal complexes contained within Q8.21We report here the first instance of a metal halide compound containedwithina cucurbituril, rather than the normal external coordination at the carbonyl O atoms. We describe the crystallisation of {[cisSnCl4(OH2)2]@Q7}2·(H3O+)6[SnCl62−]3(H2O)23,2, the favourable geometry of the endoannular complex [cisSnCl4(OH2)2]@Q7,3, the noninfluence of the crystal surrounds on the structure of3but the effects of crystal packing on solubility, and calculations of the inclusion energy and inclusion mechanism.
ISSN:1466-8033
DOI:10.1039/b107555c
出版商:RSC
年代:2001
数据来源: RSC