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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 ...
Amine gas plant at a natural gas field. Amine gas treating, also known as amine scrubbing, gas sweetening and acid gas removal, refers to a group of processes that use aqueous solutions of various alkylamines (commonly referred to simply as amines) to remove hydrogen sulfide (H 2 S) and carbon dioxide (CO 2) from gases.
The addition of hydrogen and an amino group (NR 2) using reagents other than the amine HNR 2 is known as a "formal hydroamination" reaction. Although the advantages of atom economy and/or ready available of the nitrogen source are diminished as a result, the greater thermodynamic driving force, as well as ability to tune the aminating reagent ...
For example, isophorone diamine, a precursor to the polyurethane monomer isophorone diisocyanate, is produced from isophorone nitrile by a tandem nitrile hydrogenation/reductive amination by ammonia, wherein hydrogenation converts both the nitrile into an amine and the imine formed from the aldehyde and ammonia into another amine.
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]
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 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 ...
In a similar fashion, the intermediate isocyanate can be trapped by tert-butyl alcohol, yielding the tert-butoxycarbonyl (Boc)-protected amine. The Hofmann Rearrangement also can be used to yield carbamates from α,β - unsaturated or α- hydroxy amides [ 2 ] [ 8 ] or nitriles from α,β- acetylenic amides [ 2 ] [ 9 ] in good yields (≈70%).