46710-42-3Relevant academic research and scientific papers
Excited-state intermolecular proton transfer dependent on the substitution pattern of anthracene-diurea compounds involved in fluorescent ON1-OFF-ON2 response by the addition of acetate ions
Matsumoto, Hisato,Nishimura, Yoshinobu,Arai, Tatsuo
, p. 6575 - 6583 (2017)
We report anthracene-diurea compounds which behave as anion sensors based on the fluorescence emission regulated by the substitution position on the anthracene ring. Anthracene-diurea compounds exhibit different excited-state intermolecular proton transfer (ESIPT) reactions depending on the pattern of the substituents. Three new anthracene-diurea compounds that have two phenylurea groups substituted at different positions on anthracene were synthesized. These compounds formed complexes with acetate ions through intermolecular hydrogen bonding between N-H and CO moieties in the ground state. The positions of the substituents greatly affected the excited-state intermolecular proton transfer. 1,5BPUA with urea groups at the 1 and 5 positions exhibited ESIPT reaction, which is energetically favorable for tautomer formation, in the presence of TBAAc. In contrast, 2,6BPUA with urea groups at low-electron-density positions (2 and 6 positions) showed no ESIPT reaction due to the inversion of the lowest unoccupied molecular orbital (LUMO) energy levels of the normal and tautomer states. Detailed spectroscopic measurements showed that the LUMO energy level of the normal form was lowered because the urea group acted as an electron-withdrawing group. In addition, 9,10BPUA exhibited strong electronic interactions between the two phenylurea moieties at the 9 and 10 positions, resulting in an ON1-OFF-ON2 response for acetate ions. Our findings offer guidelines for the molecular design of materials with anthracene moieties based on the substitution patterns of anthracene derivatives.
Synthesis of Stable Thiazole-Linked Covalent Organic Frameworks via a Multicomponent Reaction
Wang, Kewei,Jia, Zhifang,Bai, Yang,Wang, Xue,Hodgkiss, Sophie E.,Chen, Linjiang,Chong, Samantha Y.,Wang, Xiaoyan,Yang, Haofan,Xu, Yongjie,Feng, Feng,Ward, John W.,Cooper, Andrew I.
supporting information, p. 11131 - 11138 (2020/07/13)
The development of robust synthetic routes to stable covalent organic frameworks (COFs) is important to broaden the range of applications for these materials. We report here a simple and efficient three-component assembly reaction between readily available aldehydes, amines, and elemental sulfur via a C-H functionalization and oxidative annulation under transition-metal-free conditions. Five thiazole-linked COFs (TZ-COFs) were synthesized using this method. These materials showed high levels of crystallinity, high specific surface areas, and excellent physicochemical stability. The photocatalytic applications of TZ-COFs were investigated, and TZ-COF-4 gave high sacrificial hydrogen evolution rates from water (up to 4296 μmol h-1 g-1 under visible light irradiation) coupled with high stability and recyclability, with sustained hydrogen evolution for 50 h.
An optimized method for the synthesis of 2,6-diaminoanthracene
Kantam, Rambhoopal,Holland, Robin,Khanna, Bhanu Priya,Revell, Kevin D.
scheme or table, p. 5083 - 5085 (2011/10/09)
The reduction of 2,6-diaminoanthraquinone to 2,6-diaminoanthracene was examined under a variety of conditions. Direct reduction using zinc powder gave a mixture of the target product and 9,10-dihydro-2,6-diaminoanthracene under all the conditions examined. Protection of the starting amine, followed by borohydride reduction and deprotection, gave the target product in 14-50% yield. Finally, tin powder was used to reduce the anthraquinone to 2,6-diaminoanthrone in quantitative yield. This compound was further reduced to the target 2,6-diaminoanthracene in 55-65% yield.
Long-wavelength analogue of PRODAN: Synthesis and properties of Anthradan, a fluorophore with a 2,6-donor-acceptor anthracene structure
Lu, Zhikuan,Lord, Samuel J.,Wang, Hui,Moerner,Twieg, Robert J.
, p. 9651 - 9657 (2007/10/03)
We have synthesized the environment-sensitive fluorophores 2-cyano-6-dihexylaminoanthracene and 2-propionyl-6-dihexylaminoanthracene (Anthradan) starting from 2,6-diaminoanthraquinone. Anthradan is the benzologue of the well-known family of naphthalene 2-propionyl-6-dimethylaminonaphthalene (PRODAN) fluorophores. The additional spectral red shift of the anthracene avoids the autofluorescence of many biological systems and provides for more favorable excitation wavelengths for fluorescence applications. Furthermore, Anthradan exhibits polarity-sensitive emission comparable to that of PRODAN and displays high quantum yields in a range of solvents. Single molecules of these anthracene-containing fluorophores have been imaged in polymer hosts as a proof-of-principle.
