6492-69-9Relevant articles and documents
5,5′-alkylsubsituted indigo for solution-processed optoelectronic devices
Watanabe, Motonori,Uemura, Naoki,Ida, Shintaro,Hagiwara, Hidehisa,Goto, Kenta,Ishihara, Tatsumi
, p. 4280 - 4287 (2016)
A series of alkylated indigos were synthesized. Alkylated indigos were characterized by NMR, mass spectrometry, absorption spectra, cyclic voltammetry, and density functional theory (DFT) calculations. Propyl and butyl group substituted indigo was most soluble in chloroform and 1,2-dicrolobenzene, and these solubility were 65–89 times increased as compared to the parent indigo. DFT calculations suggested that the presence of the alkyl chains at the 5.5′-position increases the energy of the highest occupied molecular orbital, while reducing the energy of the lowest unoccupied molecular orbital. This theoretical finding was in good agreement with the experimental results. Crystal structures obtained by X-ray diffraction showed one-dimensional pi–pi stacking. Alkylated molecules were converted to leuco structure, and these structures were then converted to the corresponding indigos in the film state. After deposition of the films on TiO2/FTO substrate, oxidative photocurrents were observed.
A tunable synthesis of indigoids: Targeting indirubin through temperature
Cheek, Joshua T.,Horner, John S.,Kaller, Kaylie S.,Kinsey, Ally L.,Shriver, James A.,Sterrenberg, Summer R.,Van Vors, Madison K.,Wang, Katelyn R.
, p. 5407 - 5414 (2022/03/01)
The spontaneous conversion of 3-indoxyl to indigo is a well-established process used to produce indigo dyes. It was recently shown that some indoles, when reacted with molybdenum hexacarbonyl and cumyl peroxide, proceed through an indoxyl intermediate to produce significant amounts of indirubin through a competing mechanism. Modulation of this system to lower temperatures allows for careful tuning, leading to selective production of indirubins in a general process. A systematic assay of indoles show that electron deficient indoles work well when substituted at the 5 and 7 positions. In contrast, 6-substituted electron rich indoles give the best results whereas halogeno indoles work well in all cases. This process shows broad functional group tolerance for generally reactive carbonyl-containing compounds such as aldehydes and carboxylic acids. This journal is