Synthesis and highly efficient light-induced rearrangements of diphenylmethylene(2-benzo[b]thienyl)fulgides and fulgimides

Abstract

2-Benzo[b]thienyl fulgides and fulgimides containing bulky diphenylmethylene substituents were synthesized in the form of their ring-opened E- or Z-isomers. In contrast to the majority of known fulgides/fulgimides, that form colored ring-closed structures under UV irradiation, the obtained compounds undergo an irreversible transformation leading to decoloration of their solutions. This rearrangement with the formation of the dihydronaphthalene core appeared to be by 2–3 orders of magnitude more efficient than for the known diphenylmethylene(aryl(hetaryl))fulgides. The molecular structures of E- and Z-isomers and of products of the photoinduced rearrangement completed by 1,5-H shift reaction, 3a,4-dihydronaphtho[2,3-c]furans(pyrroles) C, were established based on the data of 1H and 13C NMR spectroscopy and X-ray diffraction studies.

Synthesis of photo- and ionochromic N-acylated 2-(aminomethylene)benzo[b]thiophene-3(2Н)-ones with a terminal phenanthroline group

“…Although studies on photoacylotropic systems have been carried out for some time [ 14 , 16 ], only within the framework of this work, a method for the preparative synthesis of photoproducts 3a – c under the influence of irradiation was developed. We applied a modified procedure using a Sweko IP65 LED emitter that had been previously developed in our studies for similar tasks [ 30 ]. For this purpose, a suspension of a yellow solid 2a – c in acetonitrile was boiled for 10–15 s and then irradiated with an emitter for 3–5 min.…”

Combined QM (MS-CASPT2)/MM studies on photocyclization and photoisomerization of a fulgide derivative in toluene solution

“…Different isomers usually present different photochromic properties, making fulgides more promising materials for many application fields. [3][4][5][6][7][8][9][10] Thus, lots of efforts have been devoted to illuminating the photocyclization and photoisomerization reactions of fulgides.…”