319016-36-9Relevant articles and documents
METHOD FOR PREPARING BENZYL AMINE COMPOUND
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Page/Page column 0045-0046, (2021/08/06)
Disclosed is a method for preparing a benzyl amine compound, i.e., synthesizing a benzyl amine compound by means of an oxidation reaction between a methylbenzene/ethylbenzene compound and arylamine by using an ionic iron (III) complex containing 1,3-di-tert-butylimidazolium cation and having a molecular formula of [(RNCHCHNR)CH][FeBr4] (R being tert-butyl) and di-t-butyl peroxide as an oxidant. The present invention is not only applicable to a methylbenzene compound containing a benzylic primary carbon-hydrogen bond but also applicable to an ethylbenzene compound containing a benzylic secondary carbon-hydrogen bond, and therefore is widely applicable. This is the first case where the preparation of a benzyl amine compound by means of an oxidation reaction between a methylbenzene/ethylbenzene compound and arylamine is implemented by an iron catalyst.
Mechanistic Studies of Hydride Transfer to Imines from a Highly Active and Chemoselective Manganate Catalyst
Freitag, Frederik,Irrgang, Torsten,Kempe, Rhett
supporting information, p. 11677 - 11685 (2019/08/20)
We introduce a highly active and chemoselective manganese catalyst for the hydrogenation of imines. The catalyst has a large scope, can reduce aldimines and ketimines, and tolerates a variety of functional groups, among them hydrogenation sensitive examples such as an olefin, a ketone, nitriles, nitro groups, and an aryl iodo substituent or a benzyl ether. We could investigate the transfer step between imines and the hydride complex in detail. We found that double deprotonation of the ligand is essential and excess base does not lead to a higher rate in the transfer step. We identified the actual hydrogenation catalyst as a K-Mn-bimetallic species and could obtain a structure of the K-Mn complex formed after hydride transfer by X-ray analysis. NMR experiments indicate that the hydride transfer is a well-defined reaction, which is first order in imine, first order in the bimetallic (K-Mn) hydride, and independent in rate from the concentration of the potassium base. We propose an outer-sphere mechanism in which protons do not seem to be involved in the rate-determining step, leading to a transiently negatively charged nitrogen atom in the substrate which reacts rapidly with HOtBu (2-methylpropan-2-ol) to produce the amine. This is based on several observations, such as no dependency of the reaction rate on the HOtBu concentration, no observable manganese amide complex, and a high reaction constant in a conducted Hammett study. Furthermore, hydrogen transfer of the catalytic cycle was experimentally probed and monitored by NMR with subsequent quantitative regeneration of the catalyst by H2.
Application of ionic iron (III) complex as catalyst in preparation of benzylamine compound
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Paragraph 0038, (2019/02/21)
The invention discloses the application of an ionic iron (III) complex as a catalyst in preparation of a benzylamine compound, that is, an ionic iron (III) complex having a formula of [(RNCHCHNR)CH][FeBr4] (R is tert-butyl) and containing 1,3-di-tert-butyl imidazolium cation is used as a catalyst, di-tert-butyl peroxide is used as an oxidizing agent, and a benzylamine compound is synthesized by oxidation reaction of a toluene/ethylbenzene compound with an aromatic amine. The application of an ionic iron (III) complex as a catalyst in preparation of a benzylamine compound has wide application range, and is applicable not only to a toluene compound containing a benzylic primary carbon-hydrogen bond but also to an ethylbenzene compound containing a benzyl secondary carbon-hydrogen bond. Thisis the first example of the preparation of a benzylamine compound by oxidation reaction of a toluene/ethylbenzene compound and an aromatic amine by an iron-based catalyst.
