5522-43-0Relevant articles and documents
Nitration of pyrene adsorbed on silica particles by nitrogen dioxide under simulated atmospheric conditions
Wang, Huimin,Hasegawa, Kiyoshi,Kagaya, Shigehiro
, p. 1923 - 1936 (1999)
Nitration of adsorbed pyrene on silica particles with nitrogen dioxide was studied under condition of room light in a simulated atmosphere. An induction period was present in the nitration process. Nitric acid formed on the silica particles acted as the catalyst, and the reaction proceeded autocatalytically. Electron-donating substituents promoted the reaction, while the electron-attracting substituents diminished it. An electrophilic nitration mechanism involving HNO2+ and HN2O4+ as electrophiles was proposed for the reaction. Nitration of adsorbed pyrene on silica particles with nitrogen dioxide was studied under condition of room light in a simulated atmosphere. An induction period was present in the nitration process. Nitric acid formed on the silica particles acted as the catalyst, and the reaction proceeded autocatalytically. Electron-donating substituents promoted the reaction, while the electron-attracting substituents diminished it. An electrophilic nitration mechanism involving HNO2+ and HN2O4+ as electrophiles was proposed for the reaction.
Regioselective Functionalization of 9,9-Dimethyl-9-silafluorenes by Borylation, Bromination, and Nitration
Murai, Masahito,Nishinaka, Naoki,Kimura, Mizuki,Takai, Kazuhiko
, (2019/05/08)
Despite the utility of 9-silafluorenes as functional materials and as building blocks, methods for efficient functionalization of their backbone are rare, probably because of the presence of easily cleavable C-Si bonds. Although controlling the regioselectivity of iridium-catalyzed direct borylation of C-H bonds is difficult, we found that bromination and nitration of 2-methoxy-9-silafluorene under mild conditions occurred predominantly at the electron-rich position. The resulting product having methoxy and bromo groups can be utilized as a building block for the synthesis of unsymmetrically substituted 9-silafluorene-containing π-conjugated molecules.
Preparation and characterization of pyrene modified uridine derivatives as potential electron donors in RNA
Frommer, Jennifer,Karg, Beatrice,Weisz, Klaus,Müller, Sabine
, p. 7663 - 7673 (2018/11/02)
Charge transfer across double stranded DNA was observed for the first time about 20 years ago, and ever since it has been the subject of a large number of studies. RNA has been hardly investigated in this regard, which not least is due to the lack of suitably functionalized ribonucleotide building blocks to serve as electron sources upon incorporation into oligoribonucleotides. We have synthesized two uridine derivatives carrying pyrene or dimethylaminopyrene linked to C5 of the nucleobase. The key to successful synthesis was the adaptation of Suzuki-Miyaura conditions to the coupling of the pyrene moiety with the ribonucleoside. Final decoration of the pyrenylated nucleosides with standard 5′-O- and 2′-O-protecting groups and subsequent 3′-O-phosphitylation delivered the building blocks for incorporation into RNA. Spectroscopic analysis of the two pyrenylated uridines and of the accordingly modified oligonucleotides showed that in particular the dimethyaminopyrene functionalized nucleoside is a promising candidate as an electron source for RNA charge transport studies.
Method for nitrating aromatic compound by using nitrate under the action of auxiliary agent
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Paragraph 0078; 0079, (2018/09/11)
The invention discloses a method for nitrating an aromatic compound by using a nitrate under the action of an auxiliary agent, and provides an aromatic nitro compound preparation method, which comprises: in the presence of an external action and an auxiliary agent, carrying out a nitrating reaction on an aromatic compound and a metal nitrate or a hydrate thereof to obtain the aromatic nitro compound, wherein the external action can cause the physical and/or chemical property change of a substance, the auxiliary agent is a substance having water absorbing ability, the external action can be mechanical force or heating, and the mechanical force can be any one selected from compression, shearing, impacting, friction, stretching, bending and vibration. According to the present invention, the method does not require any solvents so as to avoid the generation of the waste liquid; the acidic substance is not used, such that the treatment is simple after the reaction is completed, and the equipment is not damaged; the added auxiliary agent can be theoretically recycled; and the method has extremely high conversion rate and extremely high selectivity, and can be used for the nitration of conventional aromatic compounds.
