119-33-5Relevant articles and documents
Silica sulfuric acid/NaNO2 as a novel heterogeneous system for the nitration of phenols under mild conditions
Zolfigol, Mohammad Ali,Madrakian, Elahe,Ghaemi, Ezat
, p. 734 - 742 (2002)
Nitrophenols can be obtained in moderate to high yields via nitrosation-oxidation of phenols with silica sulfuric acid, NaNO2 and wet SiO2 at room temperature. In situ generation of HNO2 and a radical cation mechanism via the nitrous acid catalyzed (NAC) pathway appear to be applicable to phenol nitration using these reagents.
Evidence from (15)N Nuclear Polarisation on the Mechanisms of Rearrangement of Nitrocyclohexadienones
Ridd, John H.,Sandall, John P. B.,Trevellick, Susan
, p. 1195 - 1196 (1988)
Strong (15)N nuclear polarisation is present in both the uncatalysed and acid-catalysed rearrangements of 4-methyl-4-cyclohexa-2,5-dienone but is absent from the rearrangement of 2-methyl-2-nitrocyclohexa-3,5-dienone.
-
Hodgson,Crouch
, p. 221 (1943)
-
p-Toluenesulfonic acid catalyzed regiospecific nitration of phenols with metal nitrates
Anuradha,Srinivas,Aparna,Rao, J. Madhusudana
, p. 4933 - 4935 (2006)
Highly regiospecific mononitration of phenols and substituted phenols is accomplished employing a metal nitrate and a catalytic amount of p-toluenesulfonic acid in acetone. An exclusive ortho-selectivity was observed with excellent yields. A variety of metal nitrates were used to obtain o-nitrophenols exclusively in good to excellent yields. The use of p-toluenesulfonic acid is key for the selectivity observed.
-
Astle,Cropper
, p. 2395,2396 (1943)
-
Silica chloride/NaNO2 as a novel heterogeneous system for the nitration of phenols under mild conditions
Zolfigol, Mohammad Ali,Shirini, Farhad,Chogamarani, Arash Ghorbani
, p. 2019 - 2025 (2003)
Nitrophenols can be obtained via direct nitration of phenols with silica chloride, NANO2, and wet SiO2 at room temperature in moderate to high yields.
KHSO4 as an efficient catalytic system for the regiospecific nitration of phenols with metal nitrates
Baghernejad, Bita,Oskooie, Hossein A.,Heravi, Majid M.,Beheshtiha, Yahia Sh.
, p. 393 - 396 (2010)
Highly regiospecific mononitration of phenol and substituted phenols was accomplished employing a metal nitrate and a catalytic amount of KHSO4 in acetonitrile. An exclusive ortho-selectivity was observed with excellent yields. A variety of metal nitrates were used to obtain o-nitrophenols exclusively in good to excellent yields. The use of KHSO4 is key for the selectivity observed.
Mild and selective nitration of phenols by zeofen
Bigdeli, Mohammad A.,Heravi, Majid M.,Nemati, Firouzeh
, p. 2225 - 2230 (2007)
Certain phenols and naphthols were nitrated regioselectively with zeofen in dichloromethane as solvent at room temperature and in a short reaction time to give good yields. Copyright Taylor & Francis Group, LLC.
Zn(NO3)2·6H2O/2,4,6-trichloro-1,3,5-triazine (TCT) a mild and selective system for nitration of phenols
Nemati, Firouzeh,Kiani, Hossein
, p. 403 - 406 (2010)
Certain phenols and naphthols were nitrated regioselectively with Zn(NO3)2·6H2O/TCT in acetonitrile as solvent at room temperature and short reaction time in good yields. The reaction condition was mild. TCT is a cheap and commercially available reagent. It performed as an acid catalyst in this transformation.
Vanadium pentoxide as a catalyst for regioselective nitration of organic compounds under conventional and nonconventional conditions
Venkatesham,Reddy, K. Rajendar,Rajanna,Veerasomaiah
, p. 921 - 926 (2014)
Vanadium pentoxide is used as an efficient catalyst for regioselective nitration of aromatic compounds under conventional and nonconventional conditions such as ultrasonically assisted (USAR) and microwave-assisted reactions (MWAR). The reactions underwent smoothly and afforded good yields of products with high regioselectivity. Observed longer reaction times (about 8 h) in V2O5 catalyzed reactions reduced to (0.5/30 min) under sonication and (90 s) in the case of MWAR. When ortho position is blocked, para derivatives are obtained as end products while ortho nitro products are obtained when para position is blocked.
Self-powered continuous nitration method and device
-
Paragraph 0065-0068, (2021/07/17)
The invention belongs to the technical field of organic synthesis application, and particularly relates to a self-powered continuous nitration method and device. According to the method, a raw material (or a raw material solution) and mixed acid (or nitric acid) are added into a self-powered continuous reactor at the same time, reaction feed liquid continuously and circularly flows, is mixed and reacts in a tube pass through self-propelling force generated by stirring of an impeller, the mass and heat transfer process is completed, and the target requirement is met. According to the invention, the mass transfer and heat transfer efficiency can be improved, the heat exchange and heat transfer capabilities are improved, the reaction time is shortened, the risk degree of art is reduced, the thermal runaway risk is avoided, the reaction safety is improved, and the realization of chemical industry intrinsic safety large scale production is facilitated.
Continuous flow industrial production method of O-nitro-P-methylphenol
-
Paragraph 0021; 0024-0029; 0032-0037; 0040-0043; 0046, (2020/06/30)
The invention relates to a continuous flow industrial production method of o-nitro-p-methylphenol. The method comprises the following steps: respectively conveying p-methylphenol in a molten state atthe temperature of 40-50 DEG C and dilute nitric acid with the mass concentration of 15-25% at the temperature of 25-30 DEG C into a micro-channel reactor, carrying out a reaction for 80-120 s at thetemperature of 20-30 DEG C, and washing with a sodium bicarbonate aqueous solution after the reaction is finished, and thus obtaining an o-nitro-p-methylphenol crude product; and under the conditionsthat the vacuum degree is -0.02 MPa to -0.005 MPa and the temperature is not higher than 125 DEG C, removing low-boiling-point components, heating to 140-150 DEG C, distilling, and condensing by a stainless steel condenser, and thus obtaining the product. By adopting the production method disclosed by the invention, the reaction time is greatly shortened, the safety is high, the pollutant emissionis low, the nitric acid consumption is low, the cost is low, the post-treatment is simple, the yield is 95% or above, the purity is 98% or above, and the method is particularly suitable for industrial large-scale production.
Nitration method for aryl phenol or aryl ether derivative
-
Paragraph 0107-0112, (2020/01/03)
The invention relates to a nitration method for an aryl phenol or aryl ether derivative. The method comprises the steps of stirring an aryl phenol or aryl ether compound, nitrate, trimethylchlorosilane (TMSCl) and a copper salt in an acetonitrile solution in air at room temperature, simultaneously, monitoring extent of reaction through a TLC dot plate, removing a solvent from a mixture by a rotaryevaporator after a substrate is consumed completely, and carrying out purification through a silica-gel column, thereby obtaining a nitroolefin derivative. Meanwhile, the selective mono-nitration orbis-nitration of the substrate can be achieved through controlling equivalent weight of the nitrate. Compared with the prior art, the nitration method disclosed by the invention has the advantages that the consumption of strong-acid substances is avoided, the reaction conditions are mild, the yield is high, the applicable range of the substrate is wide, reaction activity is free of obvious attenuation after an amplified reaction, and an excellent yield is still obtained, so that the method has an obvious industrial application value.
