25796-78-5

Upstream product

• 5556-13-8 4,4′-dibromo-3,3′-bithiophene 
• 79-44-7 N,N-Dimethylcarbamoyl chloride 
• 530-62-1 1,1'-carbonyldiimidazole 

Relevant academic research and scientific papers

Rethinking Uncaging: A New Antiaromatic Photocage Driven by a Gain of Resonance Energy

Photoactivatable compounds for example photoswitches or photolabile protecting groups (PPGs, photocages) for spatiotemporal light control, play a crucial role in different areas of research. For each application, parameters such as the absorption spectrum, solubility in the respective media and/or photochemical quantum yields for several competing processes need to be optimized. The design of new photochemical tools therefore remains an important task. In this study, we exploited the concept of excited-state-aromaticity, first described by N. Colin Baird in 1971, to investigate a new class of photocages, based on cyclic, ground-state-antiaromatic systems. Several thio- and nitrogen-functionalized compounds were synthesized, photochemically characterized and further optimized, supported by quantum chemical calculations. After choosing the optimal scaffold, which shows an excellent uncaging quantum yield of 28 %, we achieved a bathochromic shift of over 100 nm, resulting in a robust, well accessible, visible light absorbing, compact new photocage with a clean photoreaction and a high quantum product (??Φ) of 893 M?1 cm?1 at 405 nm.

Asymmetric b thiopheneglyoxylic and fragrant heterocyclic the synthetic method of the compound of

The invention discloses a synthesis method of asymmetrical beta-bromodithieno heteroaromatic compounds, which comprises the following steps: reacting 4,4'-dibromo-3,3'-bithiophene used as a raw material and n-butyl lithium in anhydrous ethyl ether; then performing cyclization reaction under the action of different cyclization reagents (bis(benzenesulfonyl)thioether, N,N-dimethylformyl chloride and dimethyl dichlorosilane); and finally, performing water quenching to generate the asymmetrical beta-bromodithieno heteroaromatic compounds and symmetrical dithieno heteroaromatic compounds, wherein the asymmetrical beta-bromodithieno heteroaromatic compounds and a small amount of symmetrical dithieno heteroaromatic compounds are selectively obtained at a high yield in the presence of the n-butyl lithium; the asymmetrical beta-bromodithieno heteroaromatic compounds include 3-bromo-dithieno[2,3-b:3',4'-d]thiophene, 3-bromo-7H-cyclopentano[1,2-b:3,4-c']dithiophene-7-one and 3-bromo-7,7-dimethyl-7H-dithieno[2,3-b:3',4'-d]silole; and the symmetrical dithieno heteroaromatic compounds include dithieno[3,4-b:3',4'-d]thiophene, 7H-cyclopentano[1,2-c:3,4-c']dithiophene-7-one and 4,4-dimethyl-4H-dithieno[3,4-b:3',4'-d]silole. The synthesis process disclosed by the invention is operable, and the reaction condition is involved with a water-free, oxygen-free and low-temperature condition, thus ensuring that the invention is suitable for laboratory-scale preparation.

Selectivity of Br/Li exchange and deprotonation of 4,4′-dibromo-3, 3′-bithiophene for synthesis of symmetrical and unsymmetrical dithienoheteroaromatic rings

The novel selective synthesis of symmetrical and unsymmetrical dithienoheteroaromatic rings (DTHAs) has been developed via intramolecular cyclization of 4,4′-dibromo-3,3′-bithiophene (3). Four reaction conditions including n-BuLi/Et2O, n-BuLi/T