Ferrocene Rotary Switches Featuring 2-Pyridyl-1,2,3-triazole "Click" Chelates

Three ferrocene-based rotary switches featuring 2-pyridyl-1,2,3-triazole (pytri) "click" chelates have been developed. The rotors can be switched from a folded (syn) to extended (anti) conformation by the addition of [Cu(CH3CN)(4)](PF6) and 6,6 '-dimesityl-2,2 '-bipyridine. This extension process could be reversed by the addition of 1,4,8,11-tetraazacyclotetradecane (cyclam) to sequester the Cu(I) ions. Disappointingly, the weakness of the pytri chelates prevented the development of an electrochemically switchable system.