874-86-2Relevant academic research and scientific papers
N -Hydroxyphthalimide/benzoquinone-catalyzed chlorination of hydrocarbon C-H bond using N -chlorosuccinimide
Li, Zi-Hao,Fiser, Béla,Jiang, Biao-Lin,Li, Jian-Wei,Xu, Bao-Hua,Zhang, Suo-Jiang
supporting information, p. 3403 - 3408 (2019/04/01)
The direct chlorination of C-H bonds has received considerable attention in recent years. In this work, a metal-free protocol for hydrocarbon C-H bond chlorination with commercially available N-chlorosuccinimide (NCS) catalyzed by N-hydroxyphthalimide (NHPI) with 2,3-dicyano-5,6-dichlorobenzoquinone (DDQ) functioning as an external radical initiator is presented. Aliphatic and benzylic substituents and also heteroaromatic ones were found to be well tolerated. Both the experiments and theoretical analysis indicate that the reaction goes through a process wherein NHPI functions as a catalyst rather than as an initiator. On the other hand, the hydrogen abstraction of the C-H bond conducted by a PINO species rather than the highly reactive N-centered radicals rationalizes the high chemoselectivity of the monochlorination obtained by this protocol as the latter is reactive towards the C(sp3)-H bonds of the monochlorides. The present results could hold promise for further development of a nitroxy-radical system for the highly selective functionalization of the aliphatic and benzylic hydrocarbon C-H.
Method for synthesizing aromaticnitrile by using metalloporphyrin to catalyze aromatic olefin
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Paragraph 0133-0137, (2018/03/01)
The invention discloses a method for synthesizing aromaticnitrile by using metalloporphyrin to catalyze aromatic olefin. The method is characterized in that an aromatic alkene compound or an aromaticheterocyclic alkene compound and nitrite are reacted to generate an aromaticnitrile compound or an aromatic heterocyclic nitrile compound under the catalyzing function of the metalloporphyrin by a one-step method in air atmosphere and an acid solution system. The method has the advantages that (1) the reaction conditions are moderate, the operation is simple, the control is easy, and the yield rate is higher; (2) the high-efficiency metalloporphyrin catalyst is used, but the poisonous CN (carbon-nitrogen) negative ion reagent is not used, so that the pollution to the environment is decreased;(3) the prices of raw materials, nitrogen sources, acid reagents and the like are low, the obtaining is easy, the production cost is obviously reduced, and the method can be popularized and applied toindustrialized production.
Mild Aliphatic and Benzylic Hydrocarbon C-H Bond Chlorination Using Trichloroisocyanuric Acid
Combe, Sascha H.,Hosseini, Abolfazl,Parra, Alejandro,Schreiner, Peter R.
, p. 2407 - 2413 (2017/03/11)
We present the controlled monochlorination of aliphatic and benzylic hydrocarbons with only 1 equiv of substrate at 25-30 °C using N-hydroxyphthalimide (NHPI) as radical initiator and commercially available trichloroisocyanuric acid (TCCA) as the chlorine source. Catalytic amounts of CBr4 reduced the reaction times considerably due to the formation of chain-carrying ·CBr3 radicals. Benzylic C-H chlorination affords moderate to good yields for arenes carrying electron-withdrawing (50-85%) or weakly electron-donating groups (31-73%); cyclic aliphatic substrates provide low yields (24-38%). The products could be synthesized on a gram scale followed by simple purification via distillation. We report the first direct side-chain chlorination of 3-methylbenzoate affording methyl 3-(chloromethyl)benzoate, which is an important building block for the synthesis of vasodilator taprostene.
Direct synthesis of nitriles from cleavage of C=C double bond with nitrite as the nitrogen source and oxidant
Liu, Qiang,Fang, Bao,Bai, Xiaohui,Liu, Yuan,Wu, Yao,Xu, Guiming,Guo, Cancheng
supporting information, p. 2620 - 2623 (2016/06/01)
The transformation of the C=C bond of olefin to nitriles has been developed, using easily available NaNO2 as both the nitrogen source and oxidant. Several aryl, heterocyclic nitriles with various substituting groups could be successfully prepared in good to high yields. Based upon experimental observations, a possible reaction mechanism is proposed.
Sulfite formation versus chlorination of benzyl alcohols with thionyl chloride
Rodriguez, Deana A.,Priefer, Ronny
, p. 3045 - 3048 (2014/05/20)
Recently, we have reported the photolytic decay of a library of para-substituted dibenzylic sulfites in a Srinivasan-Griffin-Rayonet photochemical reactor. In an attempt to synthesize the complete library for that study we discovered that bis(p-methoxybenzyl) sulfite and bis(p-phenoxybenzyl) sulfite could not be formed and only their corresponding benzyl chlorides were synthesized. Thus, sulfite formation versus chlorination of a range of para-substituted benzyl alcohols with thionyl chloride was investigated. Sulfite formation was observed to be parabolically related to Swain and Lupton's Field ?-values while chloride formation was found to be linearly related to Swain and Lupton's Field ?-values.
Large-scale preparation of polyfunctional benzylic zinc reagents by direct insertion of zinc dust into benzylic chlorides in the presence of lithium chloride
Metzger, Albrecht,Argyo, Christian,Knochel, Paul
experimental part, p. 882 - 891 (2010/10/01)
Highly functionalized benzylic zinc chlorides are prepared by the direct insertion of commercially available zinc dust into the corresponding benzylic chlorides in the presence of stoichiometric amount of lithium chloride. These polyfunctional zinc organometallics react with various electrophiles leading to a broad range of functionalized products. Georg Thieme Verlag Stuttgart.
Reaction of PbO2 with Solutions of Methylbenzonitriles
Kol'tsov,Salfetnikova
, p. 389 - 393 (2007/10/03)
The yield of products formed by low-temperature oxidation of methylbenzonitriles with PbO2 in fluorosulfonic acid solutions was studied in relation to the stabilization factor of the reaction system. The revealed correlation is common for methylbenzonitriles differing in the degree of alkylation and in the oxidation mechanism.
Process for producing cyanobenzyl compounds
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, (2008/06/13)
An industrially advantageous process for producing cyanobenzyl compounds under mild conditions from relatively easily available cyanobenzylamine having a cyano group on the benzene ring or a compound thereof which is ring-substituted with a chlorine atom, a fluorine atom, etc. The process for producing a cyanobenzyl compound includes transforming an aminomethyl group of a cyanobenzylamine compound into a hydroxymethyl group, a halogenomethyl group, or an acyloxymethyl group without causing damage to a cyano group on the benzene ring. The transformation may be carried out by use of nitrosonium ions.
Oxidation of Aromatic Compounds. V. Oxidation of Substituted Benzonitriles and 2,4,6-Triaryl-1,3,5-Triazines in System HSO3F-PbO2
Rudenko,Salfetnikova,Vasil'ev
, p. 1447 - 1470 (2007/10/03)
Low-temperature oxidation of substituted benzonitriles by the system HSO3F-PbO2 proceeds with intermediate formation of cation-radicals and leads to substitution of hydrogen atoms of the methyl group or benzene ring. This reaction provides a route for preparation of chloromethylsubstituted benzonitriles, diarylmethanes, diaryls, arylfluorosulfonates and substituted benzamides with cyano groups. In the case of methyl derivatives of 2,4,6-triphenyl-1,3,5-triazine substitution of the first and then the second hydrogen atom of the same methyl group transforms it into hydroxy or chloromethyl group, or into the aldehyde function.
THE ESR SPECTRA, STRUCTURE, AND REACTIVITY OF AROMATIC RADICAL-CATIONS IN SUPERACIDS
Rudenko, A. P.
, p. 1946 - 1980 (2007/10/03)
The oxidation of aromatic compounds by lead dioxide in superacids based on fluorosulfonic acid at -75 deg C takes place by a one-electron mechanism and leads in many cases to relatively stable radical-cations.The ESR spectra, the isotropic hyperfine coupling constants, data on the reactivity of the radical-cations, and the structures of the final products from their transformations under "long-life" conditions are presented.
