Bis-thioether-Substituted Perylene Diimides: Structural, Electrochemical, and Spectroelectrochemical Properties

The synthesis and separation of the
1,6- and 1,7- isomers of N,N′-bis­(alkyl)­diadamantylthio-3,4,9,10-perylenetetracarboxylic
acid diimide are reported. Investigations of the structural, electrochemical,
spectroscopic, and spectroelectrochemical properties of the isomers
reveal a sequence of electrochemically and chemically reversible reduction
processes for both isomers. Three X-ray crystal structures are reported
including a pair of 1,6- and 1,7-isomers demonstrating the twist of
the perylene core in the solid state. Our studies thoroughly characterize
the mono- and direduced states of the two isomers allowing unequivocal
characterization of the reduced species by UV–vis and IR spectroscopic
measurements. EPR studies also allow direct identification of the
monoreduced PTCDI species and spectroscopic measurements confirm the
delocalization of electronic density around the carbonyl moieties
of the reduced species.