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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 ...
2 R-C≡N + 4 H 2 → (R-CH 2) 2 NH + NH 3 3 R-C≡N + 6 H 2 → (R-CH 2) 3 N + 2 NH 3. Such reactions proceed via enamine intermediates. [8] The most important reaction condition for selective primary amine production is catalyst choice. [1] Other important factors include solvent choice, solution pH, steric effects, temperature, and the ...
The reaction proceeds through the E i pathway, with an intramolecular, cyclic 5-membered transition state. Consequently, the elimination product is always syn and rarely occurs with 6-membered rings. (Rings with 5 or 7 or more members undergo the reaction just fine.) [6] [7] [8]
Catalytic hydrogenation [ edit ] 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 ]
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]
The Knoevenagel condensation is a key step in the commercial production of the antimalarial drug lumefantrine (a component of Coartem): [8] Final step in Lumefantrine synthesis The initial reaction product is a 50:50 mixture of E and Z isomers but beecause both isomers equilibrate rapidly around their common hydroxyl precursor, the more stable ...
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 ...
First phosphine imine-forming reaction is conducted involving treatment of the azide with the phosphine. The intermediate, e.g. triphenylphosphine phenylimide, is then subjected to hydrolysis to produce a phosphine oxide and an amine: R 3 P=NR' + H 2 O → R 3 P=O + R'NH 2. The overall conversion is a mild method of reducing an azide to an amine.