A general synthesis of macrocyclic pi-electron-acceptor systems

Colquhoun, H.M., Greenland, B.W., Zhu, Z.X., Shaw, J.S., Cardin, C.J. ORCID: https://orcid.org/0000-0002-2556-9995, Burattini, S., Elliott, J.M. ORCID: https://orcid.org/0000-0001-7469-4154, Basu, S., Gasa, T.B. and Stoddart, J.F. (2009) A general synthesis of macrocyclic pi-electron-acceptor systems. Organic Letters, 11 (22). pp. 5238-5241. ISSN 1523-7052 doi: 10.1021/ol9021782

Abstract/Summary

Cyclocondensations of aromatic diamines with 1,1'-bis(2,4-dinitrophenyl)-4,4'-bipyridinium salts afford doubly or quadruply charged, macrocyclic, N,N'-diarylbipyridinium cations. These are tolerant of a wide range of acids, bases, and nucleophiles, although they appear to undergo reversible, one-electron reduction by tertiary amines. Single-crystal X-ray analysis demonstrates the presence of a macrocycle conformation in which the 4,4'-bipyridinium and 4,4'-biphenylenedisulfonyl residues are suitably spaced and aligned for complexation with pi-donor arenes, and NMR studies in solution indeed confirm binding to 1,5-bis[hydroxy(ethoxy)ethoxy]naphthalene.