Azolium-Linked Cyclophanes: Effects of Structure, Solvent, and Counteranions on Solution Conformation Behavior
MetadataShow full item record
This paper describes the synthesis, structural characterization, and solution behavior of some xylyllinked imidazolium and benzimidazolium cyclophanes decorated with alkyl or alkoxy groups. The addition of alkyl/alkoxy chains to the cyclophanes allows for studies in chlorinated solvents, whereas previous solution studies of azolium cyclophanes have generally required highly polar solvents. The azolium cyclophanes may exist in a syn/syn conformation (azolium rings mutually syn, arene rings mutually syn) or a syn/anti conformation (azolium rings mutually syn, arene rings mutually anti). The preferred conformation is significantly affected by (i) binding of bromide (ion pairing) to the protons on theimidazolium or benzimidazolium rings, which occurs in solutions of bromide salts of the cyclophanes inchlorinated solvents, and (ii) the addition of alkoxy groups to the benzimidazolium cyclophanes. Thesestructural modifications have also led to cyclophanes that adopt conformations not previously identifiedfor similar azolium cyclophane analogues.Detailed 1H NMR studies for one cyclophane identified binding of bromide at two independent sites within the cyclophane.
Open access to this article will be available 12 months after publication via the website of the American Chemical Society. http://acswebcontent.acs.org/home.html
Showing items related by title, author, creator and subject.
Hesler, V.; Skelton, B.; White, A.; Brown, David; Baker, M. (2015)© Springer Science+Business Media Dordrecht 2015.The synthesis, structure, and conformational behaviour of three imidazolium cyclophanes that incorporate one or two 4-tert-butylphenol or 4-tert-butylanisole groups as ...
Mercury complexes of N-heterocyclic carbenes derived from imidazolium-linked cyclophanes: synthesis, structure, and reactivityBaker, M. V.; Brown, David; Haque, R. A.; Simpson, P. V.; Skelton, B. W.; White, A. H.; Williams, C. C. (2009)A range of mercury-imidazolylidene complexes have been prepared by reaction of imidazolium-linked cyclophanes with mercury(II) acetate. For cyclophanes based on meta-xylyl groups the mercury complexes are mononuclear and ...
Gandhi, Neha Sureshchandra (2011)Glycosaminoglycans (GAGs) are ubiquitous complex carbohydrate molecules present on the cell surfaces and in extracellular matrices (ECM) of vertebrate and invertebrate tissues. The interactions of sulphated GAGs such as ...