Restriction of the conrotatory motion in photo-induced 6π electrocyclic reaction: formation of the excited state of the closed-ring isomer in the cyclization. Issue 34 (27th May 2020)

• Record Type: Journal Article
• Authors: Nagasaka, Tatsuhiro; Sotome, Hikaru; Morikawa, Soichiro; Uriarte, Lucas Martinez; Sliwa, Michel; Kawai, Tsuyoshi; Miyasaka, Hiroshi
• Is Part Of: RSC advances. Volume 10:Issue 34(2020)
• Page Start: 20038
• Page End: 20045
• Publication Date: 2020-05-27
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d0ra03523h
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Restriction of the molecular geometry opens up a novel pathway in the cyclization reaction of a photochromic dithiazolylarylene derivative. Abstract : The electrocyclic reaction dynamics of a photochromic dithiazolylarylene derivative, 2, 3-dithiazolylbenzothiophene (DTA ) was investigated by using time-resolved transient absorption and fluorescence spectroscopies. The closed-ring isomer of DTA undergoes cycloreversion through the conical intersection mediating the potential energy surfaces of the excited and ground states, which is in agreement with the Woodward–Hoffmann rules for the electrocyclic reactions of 6π electron systems. On the other hand, a large portion of the open-ring isomer undergoes cyclization along the distinct reaction scheme, in which the cyclization takes place in the excited state manifold leading to the formation of the excited state of the closed-ring isomer. The suppression of the geometrical motion of DTA due to the intramolecular interaction could open a new efficient reaction pathway resulting in the formation of the electronically excited state of the product.