10541-82-9Relevant articles and documents
Electron-transfer mechanism in the N-demethylation of N,N-dimethylanilines by the phthalimide-N-oxyl radical
Baciocchi, Enrico,Bietti, Massimo,Gerini, Maria Francesca,Lanzalunga, Osvaldo
, p. 5144 - 5149 (2005)
The reactivity of the phthalimide N-oxyl radical (PINO) toward the N-methyl C-H bond of a number of 4-X-substituted N,N-dimethylanilines (X = OMe, OPh, CF3, CO2Et, CN) has been investigated by product and kinetic analysis. PINO was generated in CH3CN by reaction of N-hydroxyphthalimide (NHPI) with Pb(OAc)4 or, for the kinetic study of the most reactive substrates (X = OMe, OPh), with tert-butoxyl radical produced by 266 nm laser flash photolysis of di-tert-butyl peroxide. The reaction was found to lead to the N-demethylation of the N,N-dimethylaniline with a rate very sensitive to the electron donating power of the substituent (ρ+ = -2.5) as well as to the oxidation potential of the substrates. With appropriately deuterated N,N-dimethylanilines the intermolecular and intramolecular deuterium kinetic isotope effects (DKIEs) were measured for some substrates (X = OMe, CO2Et, CN) with the following results. First, intramolecular DKIE [(kH/kD) intra] was found to be always different and higher than intermolecular DKIE [(kH/kD)inter]; second, no intermolecular DKIE [(kH/kD)inter = 1] was observed for X = OMe, whereas substantial values of (kH/k D)inter were exhibited by X = CO2Et (4.8) and X = CN (5.8). These results, while are incompatible with a single step hydrogen atom transfer from the N-C-H bond to the N-oxyl radical, as proposed for the reaction of PINO with benzylic C-H bonds, can be nicely interpreted on the basis of a two-step mechanism involving a reversible electron transfer from the aniline to PINO leading to an anilinium radical cation, followed by a proton-transfer step that produces an α-amino carbon radical. In line with this conclusion the reactivity data exhibited a good fit with the Marcus equation and a λ value of 37.6 kcal mol-1 was calculated for the reorganization energy required in this electron-transfer process. From this value, a quite high reorganization energy (> 60 kcal mol-1) is estimated for the PINO/NHPI(-H)- self-exchange reaction. It is suggested that the N-demethylated product derives from the reaction of the α-amino carbon radical with PINO to form either a cross-coupling product or an α-amino carbocation. Both species may react with the small amounts of H2O present in the medium to form a carbinolamine that, again by hydrolysis, can be eventually converted into the N-demethylated product.
Highly Efficient Binuclear Copper-catalyzed Oxidation of N,N-Dimethylanilines with O2
Liu, Yuxia,Yan, Yonggang,Xue, Dong,Wang, Zhongfu,Xiao, Jianliang,Wang, Chao
, p. 2221 - 2225 (2020/03/23)
A binuclear copper-salicylate complex, [Cu(Sal)2(NCMe)]2 (Sal=salicylate), was found to be an active catalyst for the oxidation of N,N-dimethylanilines by O2, affording the corresponding N-methyl-N-phenylformamides as major products. The reactions were carried out with a O2 balloon and the S/C (substrate/catalyst ratio) of the model reaction could be up to 1×105, providing a practical and highly efficient catalytic protocol for accessing N-methyl-N-phenylformamides.
Method for selectively preparing N-monomethylamine compound
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Paragraph 0032-0033, (2017/08/29)
The invention discloses a method for selectively preparing an N-monomethylamine compound. The method takes an amine compound, formaldehyde and H2 as reaction raw materials; the raw materials react in a reaction medium in the presence of a compound catalyst at 30 DEG C-180 DEG C for 2h-48h, so as to obtain the N-monomethylamine compound; and the compound catalyst is composed of oxides of at least two of the following metal or oxides of least one of the following metal and at least one metal simple substance: aluminum, copper, nickel, cobalt and iron. According to the method for preparing the N-monomethylamine compound, the conversion ratio and the selectivity of N-monomethylamine are relatively high; the H2 is used as a reducing agent and is clean, cheap and environment-friendly; the catalyst utilized by the method is cheap, simple to prepare and high in catalysis efficiency; and the method has mild preparation and reaction conditions and the catalyst has no corrosiveness, is easy to separate and can be repeatedly used.
