32363-18-1Relevant academic research and scientific papers
Method for selective N-methylation of secondary amide
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Paragraph 0011, (2019/03/08)
The invention relates to a method for selective N-methylation of secondary amide. The method is characterized in that the secondary amide is in an organic solvent N, N-dimethyl formamide or dimethyl sulfoxide, trifluoroacetic acid methyl ester serves as a methylation reagent, and reaction is performed in the presence of sodium hydride, potassium tert-butoxide or sodium methylate, so as to obtain aselective N-methylated product. The method has the characteristics that generally a trifluoroacetylation product is produced when the trifluoroacetic acid methyl ester is reacted with amine compounds, however a N-methylated product can be selectively obtained when the trifluoroacetic acid methyl ester is reacted with secondary amide; the method is simple to operate, low in cost, mild in reactionconditions and high in selectivity, and avoids the use of hypertoxic methylation reagents, such as dimethyl sulfate and methyl iodide.
Re-evaluation of Cyclodextrin as a Model of Chymotrypsin: Acceleration and Inhibition of Tertiary Anilide Hydrolysis
Palmer, David R. J.,Buncel, Erwin,Thatcher, Gregory R. J.
, p. 5286 - 5291 (2007/10/02)
The hydrolysis of p-nitro-N-methyltrifluoroacetanilide (1), p-chloro-N-methyltrifluoroacetanilide (2), N-methyltrifluoroacetanilide (3), and p-methoxy-N-methyltrifluoroacetanilide (4) in the presence and absence of α- and β-cyclodextrin has been studied at 7.5 pH 10.6.For 1-3, cyclodextrin (CD) exhibits simple Michaelis-Menten saturation kinetics, with no evidence for reaction via other than 1:1 CD-substrate complexes.The behavior of CD with 4 is more complex.Moreover, CD catalyzes the hydrolysis of 1 but inhibits the hydrolysis of 2-4 across the pH range studied.The nature of the buffer catalysis in the absence of CD, exhibited in the hydrolysis of 1, also shows marked differences with that exhibited by 2-4.The data are almost simply interpreted by a mechanism in which CD accelerates formation of a tetrahedral intermediate 5; in the case of 1, the rate of breakdown of this intermediate is greater than the rate of buffer-catalyzed breakdown of the hydrolysis intermediate.The CD cavity may provide an environment complementary to the transition state for expulsion of the anilide leaving group.These results are compared with the previously reported effects of CDs on trifluoroacetanilide and phenyl ester hydrolysis and proposal of CD as a model of chymotrypsin.
