609-73-4Relevant articles and documents
Nitration of Phenylboron Dichloride with Nitronium Tetrafluoroborate. Attempted Nitration of Iodobenzene and Phenylphosphorous Dichloride
Olah, George A.,Piteau, Mark,Laali, Khosrow,Rao, Chandra B.,Farooq, Omar
, p. 46 - 48 (1990)
Electrophilic nitration of phenylboron dichloride with nitronium tetrafluoroborate and N-nitro-2,4,6-collidinium tetrafluoroborate was investigated in nitromethane solution.The reactions give 10 - 18 percent ortho, 67 - 69 percent meta, and 15 - 21 percent para isomer.NMR studies of the sytem als show the formation of PhBFCl and PhBF2 by fluoride exchange as well as their intermediate complexes with the BF4- anion.The high meta content is attributed to the nitration of uncomplexed phenylboron dihalides with the -BX2 group exhibiting an -I effect which directs the nitration significantly to the meta position.High para isomer content was obtained when phenylboron dihalides were mostly complexed by the BF4- anion, thereby reducing the -I effect of -BX2 group.The nitration of iodobenzene dichloride gave esentially only nitroiodobenzenes due to dissociation of PhICl2 and the much faster nitration of PhI as compared to PhICl2.Attempted nitration of PhPCl2 with NO2+BF4- in CH3NO2 led only to oxidation.The oxidation could not be prevented even when trimethyl phosphate was used as solvent or the milder nitrating agent MeONO2/BF3.
Low-temperature and highly efficient liquid-phase catalytic nitration of chlorobenzene with NO2: Remarkably improving the para-selectivity in O2-Ac2O-Hβ composite system
Deng, Renjie,Liu, Pingle,Luo, He'an,Ni, Wenjin,You, Kuiyi,Zhao, Fangfang
, (2020/02/26)
In this work, we developed a low-temperature and efficient approach for the highly selective preparation of valuable p-nitrochlorobenzene from the liquid-phase catalytic nitration of chlorobenzene with NO2 in O2-Ac2O-Hβ composite system. The results demonstrated that the introduction of molecular oxygen remarkably enhanced the chlorobenzene conversion and the cooperation catalysis of Hβ zeolite and Ac2O envidently improved the selectivity to para-nitro product. Under the optimized reaction conditions, 93.6 % of the selectivity to p-nitrochlorobenzene with 84.0 % of chlorobenzene conversion was obtained, and the ratio of p-nitrochlorobenzene to o-nitrochlorobenzene could reach up to 20.3. Furthermore, the selectivity distribution of nitration products was reasonably explained by the density functional theory (DFT) calculation. Finally, the possible nitration reaction pathway of chlorobenzene with NO2 was suggested in O2-Ac2O-Hβ composite catalytic system. The present work affords a new and mild nitration approach for highly selective preparation of valuable para-nitro products, and has potential industrial application prospects.
Two-Phase Electrochemical Generation of Aryldiazonium Salts: Application in Electrogenerated Copper-Catalyzed Sandmeyer Reactions
Goljani, Hamed,Tavakkoli, Zahra,Sadatnabi, Ali,Nematollahi, Davood
supporting information, p. 5920 - 5924 (2020/08/12)
The electrochemical generation of aryldiazonium salts from nitroarenes in a two-phase system (ethyl acetate/water) was reported for the first time. Some compounds including azo, azosulfone, and arylazides were prepared in good yields with good purity. Cathodically generated aryldiazoniums and anodically produced copper(Ι) ions were used to perform Sandmeyer reactions. To improve the method, an H-type self-driving cell equipped with a Zn rod as an anode was introduced and used for two-phase aryldiazonium production.
NITRATION
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Page/Page column 36; 41; 46; 64; 37; 43; 48; 69, (2020/05/28)
The present invention relates to a process for preparing a nitrated compound, comprising the step of reacting a compound (A) comprising at least one substituted or unsubstituted aromatic or heteroaromatic ring, wherein said heteroaromatic ring comprises at least one heteroatom selected from the group consisting of oxygen, sulfur, phosphor, selenium and nitrogen, with a compound of formula (I) wherein Y is selected from the group consisting of hydrogen and nitro.