Organocatalytic Transfer Hydrogenation

A Bioinspired Disulfide/Dithiol Redox Switch in a Rhenium Complex as Proton, H Atom, and Hydride Transfer Reagent

“…For example, it is used as redox reagent by glutathione reductase and thioredoxin reductase, which mediate the glutathione disulfide to glutathione conversion − or thioredoxin reduction, respectively. Synthetic analogues of such hydride donors, for example, Hantzsch esters, have been widely explored in (asymmetric) hydrogenation reactions. − …”

Iodine-promoted transfer of dihydrogen from ketones to alkenes, triphenylmethyl, and diphenylmethyl derivatives

“…Most of these reactions have now been developed using ruthenium and rhodium complexes. 7 j , k Excitingly, as a well-studied alternative to transition metal catalysts, organocatalytic transfer hydrogenations are now undergoing explosive development 1 a , e ,8 and one of the main trends is focused on the exploration of more effective transfer hydrogenation agents, which mainly include 1,4-cyclo-hexadienes, 9 a – c dihydronicotinamides, 9 d 1,4-dihydropyridines, 9 e – k and 4-substituted Hantzsch esters 9 l – n (Scheme 1b). Most of these transfer hydrogenation agents are not commercially available and require preparation.…”

TfOH-catalyzed transfer hydrogenation reaction using 1-tetralone as a novel dihydrogen source

“…14 Since then, significant advancements have been made in the reduction of various carbon–heteroatom or polarized carbon–carbon double bonds using Hantzsch ester and its analogs. 15 However, it is only in recent years that there has been a growing interest in the organocatalytic hydrogenation of nonpolarized carbon–carbon double bonds. In 2015, M. Oestreich and co-workers disclosed a boron Lewis acid B(C 6 F 5 ) 3 -catalyzed transfer hydrogenation of nonpolarized alkenes using cyclohexa-1,4-dienes as a source of hydride and proton (Fig.…”