title: Five-State Rotary Nanoswitch.
abstract: In our quest to develop artificial multistate devices, we synthesized the nanomechanical switch 1 that is characterized by a tetrahedral core equipped with four pending arms. The rotary arm with its azaterpyridine terminal is intramolecularly coordinated to a zinc(II) porphyrin station that is the terminus of another arm in 1. The two other arms carry identical sterically shielded phenanthroline stations. The 2-fold alternate addition of a copper(I) ion and [1,10]-phenanthroline (1 equiv each) results in the formation of five different switching states (State I→ State II→ State III→ State IV→ State V → State I), which force the toggling arm to move back and forth between the zinc(II) porphyrin and phenanthroline stations separated by a distance of 25 Å. All switching states constitute clean single species, except for State III, and thus are fully characterized by spectroscopic methods and elemental analysis. Finally, the initial state of nanoswitch was reset by addition of cyclam for complete removal of the copper(I) ions.
authors.affiliation: Center of Micro- and Nanochemistry and Engineering, Organische Chemie I, Universität Siegen , Adolf-Reichwein-Strasse-2, 57068 Siegen, Germany.
authors.forename: Sudhakar
authors.initials: S
authors.lastname: Gaikwad
authors.affiliation: Center of Micro- and Nanochemistry and Engineering, Organische Chemie I, Universität Siegen , Adolf-Reichwein-Strasse-2, 57068 Siegen, Germany.
authors.forename: Michael
authors.identifier: 0000-0001-8622-2883
authors.initials: M
authors.lastname: Schmittel