作者:Shigeyuki Yagi、Katsumi Maeda、Hiroyuki Nakazumi
DOI:10.1055/s-2000-6245
日期:——
A novel indolinospirothiopyran dye, 2-N,N-dimethylaminoethenyl-(1″,3″,3″-trimethylindoline-2″-spiro-2′-2′H-1′-thiopyrano)[5′,6′-c]benzo[b]pyrylium iodide (3a), was prepared by condensation of 1,2,3,3-tetramethylindolium iodide (9) with 2-N,N-dimethylaminoethenyl-3-formyl-4H-1-benzopyran-4-thione (8), and its structure was confirmed by X-ray crystallography. The spirothiopyran dye possesses its absorption band in a visible region (λmax = 499 nm) in the ring-closed form. Upon irradiation with visible light (390 < λ < 480 nm), the ring-opened form having an absorption band at the longer wavelength was formed. In the thermal decay of the ring-opened form, the original spectrum was recovered with a few isosbestic points, indicating the reversible isomerization of 3a between the spirothiopyran form and the ring-opened form.
一种新型吲哚啉螺噻喃染料,2-N,N-二甲基氨基乙烯基-(1″,3″,3″-三甲基吲哚啉-2″-螺-2′-2′H-1′-噻喃)[5′,6′-c]苯并[b]吡喃鎓碘化物(3a)、由 1,2,3,3-四甲基碘化吲哚鎓(9)与 2-N,N-二甲基氨基乙烯基-3-甲酰基-4H-1-苯并吡喃-4-硫酮(8)缩合制备而成,其结构通过 X 射线晶体学得到证实。该螺噻吡喃染料以环状闭合形式在可见光区域(δ "max = 499 nm)具有吸收带。在可见光(390 < δ" < 480 nm)照射下,形成了在较长波长处具有吸收带的开环形式。在开环形式的热衰变过程中,原始光谱得到恢复,并出现了几个等距点,这表明 3a 在螺噻吡喃形式和开环形式之间发生了可逆的异构化。