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Catalytic hydrogenation can be used to reduce amides to amines; however, the process often requires high hydrogenation pressures and reaction temperatures to be effective (i.e. often requiring pressures above 197 atm and temperatures exceeding 200 °C). [1]
Catalytic hydrogenation using platinum(IV) oxide (PtO 2) [23] or Raney nickel [24] Iron metal in refluxing acetic acid [25] Samarium diiodide [26] Raney nickel, platinum on carbon, or zinc dust and formic acid or ammonium formate [6] α,β-Unsaturated nitro compounds can be reduced to saturated amines by: Catalytic hydrogenation over palladium ...
An example of a homogeneous catalytic system is the reductive amination of ketones done with an iridium catalyst. [20] Homogenous Iridium (III) catalysts have been shown to be effective in the reductive amination of carboxylic acids , which in the past has been more difficult than aldehydes and ketones. [ 16 ]
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]
[4] [5] Hydrogenation occurs with syn stereochemistry when used on an alkyne resulting in a cis-alkene. Some of the most important transformations include the hydrogenation of ketones to alcohols or ethers (the latter product forming in the presence of alcohols and acids) [ 6 ] and the reduction of nitro compounds to amines. [ 7 ]
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 ]
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 Béchamp reduction (or Béchamp process) is a chemical reaction that converts aromatic nitro compounds to their corresponding anilines using iron as the reductant: [1] 4 C 6 H 5 NO 2 + 9 Fe + 4 H 2 O → 4 C 6 H 5 NH 2 + 3 Fe 3 O 4. This reaction was once a major route to aniline, but catalytic hydrogenation is the preferred method. [2]