Redox-switchable squaraines with extended conjugation.
[reaction: see text] The redox chemistry of pi-extended squaraines is investigated using cyclic voltammetry, in-situ spectroelectrochemistry and quantum chemical calculations. Squaraine 1 is reversibly oxidized to the radical cation and dication whereas reduction shows limited electrochemical but fully chemical reversibility. The radical cation of 1 reveals absorption bands at 1000 nm and a "two-band feature" at 1600 nm. Their implications on the intramolecular electron transfer are discussed.
Büschel
Michael
M
Universität Regensburg, Institut für Organische Chemie, Universitätsstr. 31, D-93040 Regensburg, Germany.
Ajayaghosh
Ayyappanpillai
A
Arunkumar
Easwaran
E
Daub
Jörg
J