Photochemistry of the pi-extended 9,10-bis(1,3-dithiol-2- ylidene)-9,10-dihydroanthracene system: Generation and characterisation of the radical cation, dication, and derived products

Jones, A.E.; Christensen, C.A.; Perepichka, D.F.; Batsanov, A.S.; Beeby, A.; Low, P.J.; Bryce, M.R.; Parker, A.W.

Abstract

Flash photolysis of bis[4,5-di(methylsulfanyl)1,3-dithiol-2- ylidene]-9,10-dihydroanthracene (1) in chloroform leads to formation of the transient radical cation species 1(.+) which has a diagnostic broad absorption band at lambda (max) approximate to 650 nm. This band decays to half its original intensity over a period of about 80 mus. Species 1(.+) has also been characterised by resonance Raman spectroscopy. In degassed solution 1(.+) disproportionates to give the dication 1(2+) whereas in aerated solutions the photodegradation product is the 10-[4,5-di-(methylsulfanyl)1,3-dithiol-2- ylidene]anthracene-9(10H)one (2). The dication 1(2+) has been characterised by a spectroelectrochemical study [lambda (max) (CH2Cl2) = 377, 392, 419, 479 nm] and by an X-ray crystal structure of the salt 1(2+)(ClO4-)(2), which was obtained by electrocrystallisation. The planar anthracene and 1,3- dithiolium rings in the dication form a dihedral angle of 77.2 degrees; this conformation is strikingly different from the saddle-shaped structure of neutral 1 reported previously.

Citation

Jones, A., Christensen, C., Perepichka, D., Batsanov, A., Beeby, A., Low, P., …Parker, A. (2001). Photochemistry of the pi-extended 9,10-bis(1,3-dithiol-2- ylidene)-9,10-dihydroanthracene system: Generation and characterisation of the radical cation, dication, and derived products. Chemistry - A European Journal, 7(5), 973-978. https://doi.org/10.1002/1521-3765%2820010302%297%3A5%3C973%3A%3Aaid-chem973%3E3.0.co%3B2-%23

• Journal Article Type: Article
• Publication Date: 2001-03
• Journal: Chemistry - A European Journal
• Print ISSN: 0947-6539
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 7
• Issue: 5
• Pages: 973-978
• DOI: https://doi.org/10.1002/1521-3765%2820010302%297%3A5%3C973%3A%3Aaid-chem973%3E3.0.co%3B2-%23