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In chemistry, the hydrogenation of carbon–nitrogen double bonds is the addition of the elements of dihydrogen (H 2) across a carbon–nitrogen double bond, forming amines or amine derivatives. [1] Although a variety of general methods have been developed for the enantioselective hydrogenation of ketones, [ 2 ] methods for the hydrogenation of ...
The intermediate imine can be isolated or reacted in-situ with a suitable reducing agent (e.g., sodium borohydride) to produce the amine product. [2] Intramolecular reductive amination can also occur to afford a cyclic amine product if the amine and carbonyl are on the same molecule of starting material. [4]
For example, in the three-component coupling of aldehydes, amines, and activated alkenes, the aldehyde reacts with the amine to produce an imine prior to forming the aza-MBH adduct, as in the reaction of aryl aldehydes, diphenylphosphinamide, and methyl vinyl ketone, in the presence of TiCl 4, triphenylphosphine, and triethylamine: [19]
Amine ligation followed by deprotonation by base produces the palladium amide. (Chelating systems have been shown to undergo these two steps in reverse order, with base complexation preceding amide formation.) This key intermediate reductively eliminates to produce the product and regenerate the catalyst.
The catalytic hydrogenation of nitriles is often the most economical route available for the production of primary amines. [3] Catalysts for the reaction often include group 10 metals such as Raney nickel , [ 4 ] [ 5 ] [ 6 ] palladium black , or platinum dioxide . [ 1 ]
Amine. In chemistry, amines (/ ə ˈ m iː n, ˈ æ m iː n /, [1] [2] UK also / ˈ eɪ m iː n / [3]) are compounds and functional groups that contain a basic nitrogen atom with a lone pair.Formally, amines are derivatives of ammonia (NH 3 (in which the bond angle between the nitrogen and hydrogen is 170°), wherein one or more hydrogen atoms have been replaced by a substituent such as an ...
The reaction process begins with diazotization of the amine by nitrous acid. The diazonium group is a good leaving group, forming nitrogen gas when displaced from the organic structure. This displacement can occur via a rearrangement (path A), in which one of the sigma bonds adjacent to the diazo group migrates. This migration results in an ...
The Hofmann rearrangement (Hofmann degradation) is the organic reaction of a primary amide to a primary amine with one less carbon atom. [1] [2] [3] The reaction involves oxidation of the nitrogen followed by rearrangement of the carbonyl and nitrogen to give an isocyanate intermediate.