Transfer hydrogenation and transfer hydrogenolysis. V. Hydrogen transfer from amines, ethers, alcohols, and hydroaromatic compounds to olefins catalyzed by chlorotris(triphenylphosphine)rhodium(I)

1975 ◽  
Vol 40 (2) ◽  
pp. 237-240 ◽  
Author(s):  
Takeshi Nishiguchi ◽  
Kazuyuki Tachi ◽  
Kazuo Fukuzumi
Keyword(s):  
Hydrogen Transfer ◽  
Transfer Hydrogenation

scholarly journals New Bifunctional Bis(azairidacycle) with Axial Chirality via Double Cyclometalation of 2,2′-Bis(aminomethyl)-1,1′-binaphthyl

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1165
Author(s):  
Yasuhiro Sato ◽  
Yuichi Kawata ◽  
Shungo Yasui ◽  
Yoshihito Kayaki ◽  
Takao Ikariya
Keyword(s):  
Hydrogen Transfer ◽  
Bond Cleavage ◽  
Enantiomeric Excess ◽  
Transfer Hydrogenation ◽  
Catalyst Precursor ◽  
Asymmetric Catalysts ◽  
Axially Chiral ◽  
Diastereomeric Mixture ◽  
Raney Ni ◽  
Half Sandwich

As a candidate for bifunctional asymmetric catalysts containing a half-sandwich C–N chelating Ir(III) framework (azairidacycle), a dinuclear Ir complex with an axially chiral linkage is newly designed. An expedient synthesis of chiral 2,2′-bis(aminomethyl)-1,1′-binaphthyl (1) from 1,1-bi-2-naphthol (BINOL) was accomplished by a three-step process involving nickel-catalyzed cyanation and subsequent reduction with Raney-Ni and KBH4. The reaction of (S)-1 with an equimolar amount of [IrCl2Cp*]2 (Cp* = η5–C5(CH3)5) in the presence of sodium acetate in acetonitrile at 80 °C gave a diastereomeric mixture of new dinuclear dichloridodiiridium complexes (5) through the double C–H bond cleavage, as confirmed by 1H NMR spectroscopy. A loss of the central chirality on the Ir centers of 5 was demonstrated by treatment with KOC(CH3)3 to generate the corresponding 16e amidoiridium complex 6. The following hydrogen transfer from 2-propanol to 6 provided diastereomers of hydrido(amine)iridium retaining the bis(azairidacycle) architecture. The dinuclear chlorido(amine)iridium 5 can serve as a catalyst precursor for the asymmetric transfer hydrogenation of acetophenone with a substrate to a catalyst ratio of 200 in the presence of KOC(CH3)3 in 2-propanol, leading to (S)-1-phenylethanol with up to an enantiomeric excess (ee) of 67%.

A CONVENIENT “HYDROGEN TRANSFER” HYDROGENATION OF TESTOSTERONE

1989 ◽  
Vol 21 (4) ◽  
pp. 515-517 ◽  
Author(s):  
Dimitris M. Spyriounis ◽  
George Ikonomidis ◽  
Vassilis J. Demopoulos
Keyword(s):  
Hydrogen Transfer ◽  
Transfer Hydrogenation

Transfer Hydrogenation of Carbonyl Compounds and Alkenes Catalyzed by Ruthenium(II)-N-Heterocycle Carbene Complexes

2007 ◽  
Vol 72 (8) ◽  
pp. 1037-1045 ◽  
Author(s):  
Marianna Fekete ◽  
Ferenc Joó
Keyword(s):  
Carbonyl Compounds ◽  
Hydrogen Transfer ◽  
Transfer Hydrogenation ◽  
Unsaturated Alcohol ◽  
Two Phase ◽  
Carbene Complexes ◽  
Saturated Alcohol ◽  
Catalytic Activities ◽  
Saturated Aldehyde ◽  
Phase Mixture

The Ru(II)-N-heterocycle carbene complexes [RuCl2(η6-p-cymene)L] (L = 1-butyl-3-methylimid- azol-2-ylidene) and [RuCl(η6-p-cymene)L(pta)]Cl (pta = 1,3,5-triaza-7-phosphaadamantane) showed excellent catalytic activities (with turnover frequencies up to 1116 h-1) in the hydrogen transfer reduction of cinnamaldehyde and several ketones using propan-2-ol/KOH as a H-donor. Similar hydrogenations of trans-stilbene and cyclohexene were characterized by low conversions. The hydrogenation of 4-phenylbut-3-en-2-one and cinnamaldehyde proceeded with moderate selectivities of the formation of the saturated alcohol or of the of C=C hydrogenation (giving saturated ketone or saturated aldehyde). In the case of cinnamaldehyde, the unsaturated alcohol is initially formed; however, subsequent redox isomerization to the saturated aldehyde with the same catalyst diminishes its yield. The hydrogen transfer from formate to 4-phenylbut-3-en-2-one in an aqueous-organic two-phase mixture was also demonstrated.

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