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In chemistry, transfer hydrogenation is a chemical reaction involving the addition of hydrogen to a compound from a source other than molecular H 2.It is applied in laboratory and industrial organic synthesis to saturate organic compounds and reduce ketones to alcohols, and imines to amines.
[1] [2] Mechanism of one type of carbonyl addition hydrogen auto-transfer reaction involving hydrometalation (step 2). [ 3 ] Hydrogen auto-transfer , also known as borrowing hydrogen , is the activation of a chemical reaction by temporary transfer of two hydrogen atoms from the reactant to a catalyst and return of those hydrogen atoms back to a ...
The transition state of two transfer-hydrogenation reactions from ruthenium-hydride complexes onto carbonyls. Transfer hydrogenation uses hydrogen-donor molecules other than molecular H 2. These "sacrificial" hydrogen donors, which can also serve as solvents for the reaction, include hydrazine, formic acid, and alcohols such as isopropanol. [18]
An alternative, innovative and highly promising approach to convert LOHC-bound hydrogen into electricity is proposed recently. [1] The new unloading sequence consists of an almost thermoneutral catalysed transfer hydrogenation step converting ketone to secondary alcohol by contacting hydrogen-rich carrier (H18-DBT), and the secondary alcohol is then directly consumed in a PEMFC (direct ...
The second is an organocatalytic transfer hydrogenation system based on Hantzsch esters and a chiral Brønsted acid. In this case, the authors envision a mechanism where the isoquinoline is alternately protonated in an activating step, then reduced by conjugate addition of hydride from the Hantzsch ester. [63]
The Shvo catalyst is an organoruthenium compound that catalyzes the hydrogenation of polar functional groups including aldehydes, ketones and imines. The compound is of academic interest as an early example of a catalyst for transfer hydrogenation that operates by an "outer sphere mechanism". [1]
In 1999, Chul-Ho Jun and Hyuk Lee reported the first example of hydroacylation through shuttle catalysis. [5] In this example, 3-methyl-2-aminopyridine was used to activate the acyl group as well as coordinate to the rhodium catalyst, promoting C–C bond cleavage to eventually enable aldehyde transfer from a ketone to an alkene.
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 ...