名称:
Synthesis and properties of photochromic biindenylidenedione derivatives containing thiophene groups, and new insights into the reaction of 2,2′-biindanylidene-1,1′,3,3′-tetraone with Grignard reagent
摘要:
Three indenone derivatives (1: 2-[3'-hydroxy-3'-(2-thienyl)indanone-2'-yl]-3-(2-thienyl)indenone; 2: trans-anti-3,3'-(2-thienyl)-3,3'-dihydroxy-[2,2'-bi-1H-indene]-1,1'dione and 3: trans-syn-3,3'-(2-thienyl)-3,3'-dihydroxy-[2,2'-bi-1H-indene]-1,1'-dione) were obtained in a one-pot reaction of 2,2'-biindanylidene-1,1',3,3'-tetraone with 2-thienylmagnesium bromide. Their structures were characterized by means of IR, H-1 NMR, MS, elemental analysis, and X-ray crystallography. The photochromic and photoinduced radical behaviors of these compounds were investigated by means of solid UV-vis spectroscopy and electron spin resonance (ESR) spectroscopy. The results show that compounds 2 and 3 exhibit photochromism in the solid state, whereas compound I does not. The relationship between the crystal structures and photochemical properties is also discussed. Based on the formation and product distribution of compounds 1, 2, and 3, a plausible pathway is suggested for the reaction of 2,2'-biindanylidene-1,1',3,3'-tetraone with 2-thienylmagnesium bromide. The findings obtained in this study also provide new insights into the addition-oxidation mechanism for the reaction of 2,2'-biindanylidene-1,1',3,3'-tetraone with Grignard reagent. (C) 2008 Elsevier B.V. All rights reserved.