Instant Photochromism Caused by Radical Formation in Photocatalytic Decarboxylation of Dihydrothiazole Derivative

Main observation and conclusion A pair of new enantiomeric compounds,(R)/(S)-1,3,5-benzene-triyl-2,2',2”-tris(4,5-dihydrothiazole-4-carboxylic acid)(H3LRRR and H3LSSS)are synthesized in one step synthetic route with high yield.Instant photochromism has been investigated to elaborate the photocatalytic decarboxylation of the dihydrothiazole derivative by electron paramagnetic resonance spectroscopy(EPR),photoluminescence(PL),FT-IR,high resolution mass spectra,X-ray photoelectron spectroscopy and UV-Vis spectroscopic techniques.The results indicate that the photochromic transformation is originated from the formation of the radical during the photocatalytic decarboxylation of the 4,5-dihydrothiazole-4-carboxylic acid units.