Phosphine-NHC Manganese Hydrogenation Catalyst Exhibiting a Non-Classical Metal-Ligand Cooperative H2 Activation Mode

Article abstract of DOI:10.1002/anie.201901169

Deprotonation of the Mn^I NHC-phosphine complex fac-[MnBr(CO)₃(κ²P,C-Ph₂PCH₂NHC)] (2) under a H₂ atmosphere readily gives the hydride fac-[MnH(CO)₃(κ²P,C-Ph₂PCH₂NHC)] (3) via the intermediacy of the highly reactive 18-e NHC-phosphinomethanide complex fac-[Mn(CO)₃(κ³P,C,C-Ph₂PCHNHC)] (6 a). DFT calculations revealed that the preferred reaction mechanism involves the unsaturated 16-e mangana-substituted phosphonium ylide complex fac-[Mn(CO)₃(κ²P,C-Ph₂P=CHNHC)] (6 b) as key intermediate able to activate H₂ via a non-classical mode of metal-ligand cooperation implying a formal λ⁵-P–λ³-P phosphorus valence change. Complex 2 is shown to be one of the most efficient pre-catalysts for ketone hydrogenation in the Mn^I series reported to date (TON up to 6200).

Full text of DOI:10.1002/anie.201901169

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Accepted Article
Title: Phosphine-NHC Manganese Hydrogenation Catalyst Exhibiting a
Non-Classical Metal-Ligand Cooperative H2 Activation Mode
Authors: Ruqaya Buhaibeh, Oleg A. Filippov, Antoine Bruneau-Voisine,
Jérémy Willot, Carine Duhayon, Dmitry A. Valyaev, Noël
Lugan, Yves Canac, and Jean-Baptiste Sortais
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10.1002/anie.201901169
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Phosphine-NHC Manganese Hydrogenation Catalyst Exhibiting
a Non-Classical Metal-Ligand Cooperative H2 Activation Mode
Ruqaya Buhaibeh,[a] Oleg A. Filippov,[b] Antoine Bruneau-Voisine,[a,c] Jérémy Willot,[a] Carine
Duhayon,[a] Dmitry A. Valyaev,*,[a] Noël Lugan,*,[a] Yves Canac*,[a] and Jean-Baptiste Sortais*,[a,d]
Abstract: Deprotonation of the Mn(I) NHC-phosphine complex fac-
[MnBr(CO)3(κ2P,Ĉ-Ph2PCH2NHC)] (2) under a H2 atmosphere readily
gives the hydride fac-[MnH(CO)3(κ2P,Ĉ-Ph2PCH2NHC)] (3) via the
intermediacy of the highly reactive 18-e NHC-phosphinomethanide
ligand arm though a mechanism in which the rearomatization of
the pyridine moiety actually plays a key role (Scheme 1, (c)).[9]
We report herein that
a non-classical metalla-substituted
phosphonium ylide obtained upon C–H deprotonation of a
chelating NHC-phosphine ligand in the Mn coordination sphere
can easily activate H2 (Scheme 1, (d)), thus providing the first
evidence of the involvement of5-P species in metal-ligand
cooperation. Thanks to this non-classical mode of H2 activation,
the NHC-phosphine Mn(I) complex behaves as a powerful
catalyst for the hydrogenation of ketones.
complex
fac-[Mn(CO)3(κ3P,C,Ĉ-Ph2PCHNHC)]
(6a).
DFT
calculations revealed that the preferred reaction mechanism involves
the unsaturated 16-e mangana-substituted phosphonium ylide
complex
intermediate able to activate H2 via a non-classical mode of metal-
ligand cooperation implying a formal 5-P 3-P phosphorus
fac-[Mn(CO)3(κ2P,Ĉ-Ph2P=CHNHC)]
(6b)
as
key
–
valence change. Complex 2 is shown to be one of the most efficient
pre-catalysts for ketone hydrogenation in the Mn(I) series reported to
date (TON up to 6200).
Cooperative activation of inert chemical bonds is a topical
concern in modern chemistry and homogeneous catalysis. Since
the discovery of Shvo-type catalysts,[1] a wide variety of
transition metal complexes bearing non-innocent ligands was
exploited for E–H bond activation,[2] recently supplemented by
related reactivity of frustrated Lewis pairs[3] and main-group
ambiphiles.[4] Among all these transformations, the activation of
H2 is of utmost importance because of its essential role in
catalytic [transfer] hydrogenation[5] and hydrogen borrowing[6]
processes relevant in fine chemicals industry. While the seminal
contribution of Noyori and coll. involving an amide/amine
interplay in the coordination sphere of transition metals (Scheme
1, (a)) still is the most ubiquitous system for heterolytic H2
splitting,[7] similar transformations implying phosphorous
analogues remain scarce (Scheme 1, (b)).[8] By contrast, the
association of N- and P-moieties for such application was more
developed (Scheme 1, (c)). In this regard, as mostly
demonstrated in pincer-type series, the species resulting from
deprotonation of the methylene bridge in phosphine-pyridine
complexes are capable to activate H2 across the metal and the
Scheme 1. H2 activation by non-innocent ligands via metal-ligand cooperation.
Compassing our recent investigations on the application of Mn(I)
complexes supported by bidentate ligands in hydrogenation-type
catalysis,[10] we turned our attention to the use of ligand systems
now associating phosphine and NHC donors. Complex 2 was
readily obtained in 86% yield from the corresponding phosphine-
imidazolium salt [1]OTs[11] through the sequential addition of
KHMDS and [Mn(CO)5Br] (Scheme 2). According to IR and NMR
spectroscopy, the air stable complex 2 forms as a single isomer
2
(P71.3 ppm (s), C 197.7 ppm (d, JPC = 17.5 Hz, CN C)),
2
presenting a facial arrangement of the three carbonyl ligands as
confirmed by an XRD study (Figure 1a).[12]
[a]
[b]
R. Buhaibeh, Dr. A. Bruneau-Voisine, Dr. J. Willot, Dr. C. Duhayon,
Dr. D. A. Valyaev, Dr. N. Lugan, Dr. Y. Canac, Prof. Dr. J.-B. Sortais
LCC-CNRS, Université de Toulouse, CNRS, UPS, Toulouse, France
205 route de Narbonne, 31077 Toulouse Cedex 4, France
E-mail: dmitry.valyaev@lcc-toulouse.fr, noel.lugan@lcc-toulouse.fr,
yves.canac@lcc-toulouse.fr, jean-baptiste.sortais@lcc-toulouse.fr
Dr. O. A. Filippov,
A. N. Nesmeyanov Institute of Organoelement Compounds (INEOS)
Russian Academy of Sciences
28 Vavilov str., GSP-1, B-334, Moscow, 119991, Russia
Dr. A. Bruneau-Voisine,
To explore the chemical behaviour of 2 towards H2, the latter
complex was first reacted with KHMDS in toluene at 0 °C under
1 atm. of H2. Under these conditions, 2 was rapidly converted
into the corresponding Mn(I) hydride complex 3 (Scheme 2, up)
isolated in 78% yield, standing up as the first example of a Mn
1
hydride complex bearing a NHC ligand. The H NMR spectrum
2
of 3 displays a doublet at H –7.25 ppm with a JPH constant of
[c]
[d]
53.8 Hz agreeing with the cis arrangement of hydride and
phosphine moieties. The 31P NMR signal of 3 (P 94.2 ppm) was
found shifted downfield compared to the bromide precursor 2 (P
71.3 ppm). A similar trend was observed for the carbenic
Univ Rennes, CNRS, ISCR – UMR 6226, F-35000, Rennes, France
Prof. Dr. J.-B. Sortais
Institut Universitaire de France
1 rue Descartes, F-75231 Paris Cedex 05, France
resonance in the 13C NMR spectrum (3: C 205.4 ppm (d, 2JPC
14.3 Hz); 2: C 197.7 ppm (d, 2JPC = 17.5 Hz)). The facial
=
Supporting information for this article is given via a link at the end of
the document.
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10.1002/anie.201901169
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spectra respectively, consistent with the presence of a CH group
in the α-position of P-atom and confirming that the deprotonation
does take place at the CH2 bridge. Noticeably, while the 13C{1H}
NMR spectrum displays three distinct resonances for CO ligands
at standard chemical shifts, the carbenic carbon atom appears
2
to be strongly shielded (C 178.0 ppm, d, JPC = 14.2 Hz) by ca.
20-25 ppm compared to the antecedent complexes 2-5.
Scheme 2. Synthesis and reactivity of NHC-phosphine Mn(I) complex 2.
(a)
(b)
arrangement of the three carbonyls co-ligands of complex 3 was
univocally confirmed by an XRD study (Figure 1b). Noteworthy,
performing the previous reaction under D2 atmosphere led to
complex 3D2 with a full incorporation of deuterium at the hydride
(Mn–D) and at the CH2 positions (CH–D, see the S.I.).
In order to further characterize the acidic site in the complex 2,
i.e. the one that undergoes the deprotonation reaction, different
trapping experiments were carried out. For this purpose, complex
2 was first treated with KHMDS followed by the addition of an
excess of classical alkylating agent such as MeI.[13] The resulting
complex 4 showing methylation of the carbon atom linking the
phosphine and NHC moieties was isolated as a mixture of two
diastereomers (ratio 6:1) differing by the position of the methyl
group with respect to the iodine atom (Scheme 2, middle). Both
isomers of complex 4 (major isomer: P 73.0 ppm (s); C 195.9
(c)
(d)
Figure 1. Molecular geometry of complexes fac-2 (a), fac-3 (b), fac-4 (c), and
5 (d) (30% probability ellipsoids, aryl groups represented as a wireframe).
Despite all our efforts, single crystals of complex 6 could not be
obtained. Its structure was therefore investigated by theoretical
calculations. DFT study at the BP86/def2-TZVP level revealed five
minima on the PES. The global minimum corresponds to the
strongly distorted octahedral 18-e complex fac-[Mn(CO)3(κ3P,C,Ĉ-
Ph2PCHNHC)] (6a, Figure 2 (left)) featuring a facially coordinated,
5-e donor, NHC-phosphinomethanide ligand.[16,17] Calculated
metrical parameters within the MnPC moiety are comparable to
2
ppm (d, JPC = 16.6 Hz, CN C)) display similar spectroscopic
2
features compared to the bromide precursor 2. An XRD analysis
of 4 evidenced the presence of the anti-isomer in the solid state
(Figure 1c). In a second time, the deprotonated species was
exposed to CO2 (1 atm.) affording the complex 5 in 89% yield
(Scheme 2, bottom) whose solid state structure highlights the
existence of a tripodal NHC-phosphine-carboxylate scaffold with
a facial arrangement of the carbonyl ligands (Figure 1d).[14,15]
These results clearly indicated that the deprotonation of 2 occurs
at the CH2 bridge forming a sufficiently nucleophilic carbon
species to react with electrophiles such as MeI or CO2.
those
experimentally
found
in
the
related
[(κ2P,C-
Ph2PCH2)Mn(CO)4] complex.[16a] The other minima correspond to
the four possible isomers – two fac and two mer – of square
pyramidal 16-e [Mn(CO)3(κ2P,Ĉ-Ph2P=CHNHC)] complex 6b
showing an unusual bidentate NHC-phosphonium ylide ligand
Yet, after proving the involvement of
a deprotonated
intermediate 6 of general formulae [Mn(CO)3(Ph2PCHNHC)] for
the formation of complexes 3-5 from 2, arose the question of its
structure. Despite its relative instability (t1/2 of ca. 0.5 h at r.t.,
decomposition at –30 °C over 16 h), optimization of reaction
parameters allowed to prepare suitable samples for complete
spectroscopic characterization. The IR spectrum of 6 in toluene
exhibits two CO bands at 1993 (s) and 1901 (vs) cm–1 consistent
with the presence of three CO ligands in a facial arrangement.
The 31P{1H} NMR spectrum recorded in a [D8]toluene solution at
–30 °C revealed the complete conversion of 2 (P 71.7 ppm) into
6, the latter being characterized by a shielded chemical shift at
P 51.6 ppm. The deprotonation site was finally revealed by the
concomitant presence of doublets at H 3.55 (2JPH = 8.6 Hz, 1H)
Figure 2. Structures and DFT optimized geometries of complexes 6a and fac-
6b (BP86/def2-TZVP, toluene SMD model).
1
and at C 22.7 ppm (1JPC = 18.2 Hz) in the H and 13C{1H} NMR
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(see the SI for details). The most thermodynamically stable
isomer of NHC-ylide complexes fac-6b, yet being destabilized by
+7.5 kcal.mol–1 relative to 6a, is depicted in Figure 2 (right). The
calculated P–C bond length in fac-6b (1.741 Å) is consistent with
an ylidic P–C bond, in agreement with experimental values found
in toluene or t-AmOH the loading of 2 could be decreased to 0.1
mol% at 60 °C or even to 0.05 mol% at 100 °C keeping a full
conversion. A maximum TON of 6200 was achieved with 0.01
mol% in t-AmOH, showing that this catalyst is competitive with
the best Mn-based systems for this reaction reported to date[23b-c]
No reaction took place in the presence of the sole hydride
complex 3, while catalytic activity could be restored in the
presence of base, showing its critical role in the catalytic
cycle.[10,23,24]
in
a related iron-substituted phosphonium ylide complex
(1.766(11) Å)[18] and in other metal complexes bearing more
conventional NHC-ylide ligands (1.750(7)-1.794(8) Å).[19]
According to ETS-NOCV study, the P–Mn bond in fac-6b is
significantly stronger than that in complexes 2-3 featuring a
We then enlarged the synthetic scope of this catalytic
conventional phosphine-metal dative bond (see the SI for details). transformation ( Table 1) and found that a large variety of
Very significantly, the relatively constrained coordination of
the NHC-phosphinomethanide ligand in 6a results in a strong
distortion of yaw angle θ[20] for the NHC ligation (6a: θ 29.5° vs.
2-4, 6b: 6.2-7.2°). Considering that the shielding of the 13C NMR
chemical shift of carbenic carbon atoms in metal complexes
increases as the value of θ,[21] the signal recorded at C 178.0
ppm for 6 in solution (vide supra) appears to be totally consistent
with the most stable structure 6a. In addition, computed 13C
NMR chemical shift for the carbenic atom in complex 6a (C
181.5 ppm) matches well with the experimental value (C 178.0
ppm), a value significantly different from that computed for
complex fac-6b (C 215.1 ppm) (see Table S5 for details), thus
the deprotonation product of 2 was be assigned to complex 6a.
The mechanism of H2 activation by 6a was then investigated by
DFT calculations. Among the different activation pathways
considered, the process showing the lowest energy profile is
depicted in Scheme 3 (see the SI for alternative mechanisms).
Complex 6a is first converted into the 16-e NHC-ylide species
fac-6b with an energy barrier of 15.7 kcal.mol–1 (TS1) which then
coordinate H2 to form the dihydrogen complex 7 via a TS2 of
aryl(alkyl)ketones could be readily reduced (entries 1-18),
including sterically hindered representatives (entries 2-4, 7)
inaccessible using our previous Mn catalyst based on
a
chelating phosphine-aminopyridine ligand.[10c] Interestingly, the
reaction is tolerant to aryl groups substituted with halogen atoms
(F, Cl, Br, I) and CF3 moiety (entries 9-14). Aliphatic 2-decanone
was hydrogenated in the efficient manner albeit at 100 °C (entry 19).
The heterocyclic substrates bearing potentially coordinating groups
can also be reduced (entries 20-22) but with lower efficiency.
Table 1. Scope of hydrogenation of ketones catalyzed by Mn complex 2[a].
Entry
Substrate
R = Me
Cat. (%)
Method
Conv.[b]
1
2
3
0.1
0.5
A
A
A
>98 (91)
>98 (89)
90 (85)
R = i-Pr
R = t-Bu
0.5[c]
4
5
6
7
8
R = 2-Me
R = 3-Me
R = 4-Me
R = 2,4,6-Me3
R = 4-OMe
R = 4-F
R = 4-Cl
R = 2-Br
R = 4-Br
R = 4-I
0.5[d]
0.2[d]
0.1
A
A
A
A
B
A
A
A
B
A
A
>98 (93)
>98 (97)
>98 (93)
>98 (72)
>98 (98)
>98 (97)
>98 (83)
94 (81)
0.5[c]
0.5[d]
0.1
9
10
11
12
13
14
0.5[d]
0.2[d]
0.2[d]
0.5[e]]
0.5[c]
11.3 kcal.mol–1.[22] Finally, complex
7 undergoes a facile
>98 (99)
94 (79)
>98 (92)
heterolytic cleavage of the H–H bond through the low-lying
transition state TS3 with an energy barrier of only 3.2 kcal.mol–1
affording finally the experimentally observed Mn(I) hydride 3.
Having established that complex 2 could effectively activate H2 in
basic conditions, we next focused our attention on the
hydrogenation of ketones as benchmark reaction.[10a,23]
Gratifyingly, at 60 °C, in toluene, in the presence of 1.0 mol% of
2 and 2.0 mol% of KHMDS, acetophenone was fully reduced to
1-phenylethanol (see Table S1 for optimization details). Notably,
R = 4-CF3
15
16
0.2[d]
0.2[d]
0.2[d]
B
A
B
90 (65)
66 (52)
78 (71)
17
18
0.5[d]
0.5[c]
A
A
50 (37)
19
20
>98 (98)
1.0[f]
1.0[f]
1.0[f]
A
B
B
75
40
10
21
22
[a] Typical procedure: an autoclave was charged with pre-catalyst 2 (0.1
mol%), ketone (2.0 mmol), base (1.0 mol%; A: t-BuOK, B: KHMDS),
solvent (2 mL, A: t-AmOH, B: toluene), in this order and then rapidly
pressurized with H2 (50 bar) and heated under stirring at 60 °C for 20h; [b]
conversion determined by 1H NMR, isolated yield in parenthesis; [c] 2% of
base, 100 °C; [d] 2% of base; [e] 5% of KOH; [f] 5% of base, 100 °C, 72h
Scheme 3. The preferred mechanism of H2 activation with 6 (BP86/def2-TZVP,
toluene SMD model, Gibbs energies are given in kcal.mol–1 and referred to 6a.
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Roisnel, D. A. Valyaev, N. Lugan, J.-B. Sortais, Adv. Synth. Catal. 2018,
360, 676; d) D. Wei, A. Bruneau-Voisine, D. A. Valyaev, N. Lugan, J.-B.
Sortais, Chem. Commun. 2018, 54, 4302.
In conclusion, we have shown that a Mn(I) complex of a
easily accessible bidentate phosphine-NHC ligand can be
selectively deprotonated at the carbon position located between
the two donor moieties to afford an original 18-e NHC-
[11] M. J. Bitzer, A. Pöthig, C. Jandl, F. E. Kühn, W. Baratta, Dalton Trans.
2015, 44, 11686.
phosphinomethanide complex. The latter can serve as
a
[12] CCDC 1891858-1891861 contain full crystallographic data for this
paper. These data can be obtained free of charge from the Cambridge
Crystallographic Data Centre at www.ccdc.cam.ac.uk/data_request/cif.
[13] For methylation of dearomatized PNP complex, see: J. I. van der Vlugt,
E. A. Pidko, D. Vogt, M. Lutz, A. L. Spek, Inorg. Chem. 2009, 48, 7513.
[14] a) C. A. Huff, J. W. Kampf, M. S. Sanford, Organometallics 2012, 31,
4643; b) M. Vogt, M. Gargir, M. A. Iron, Y. Diskin-Posner, Y. Ben-David,
D. Milstein, Chem. Eur. J. 2012, 18, 9194; c) M. Vogt, A. Nerush, M. A.
Iron, G. Leitus, Y. Diskin-Posner, L. J. W. Shimon, Y. Ben-David, D.
Milstein, J. Am. Chem. Soc. 2013, 135, 17004; d) C. A. Huff, M. S.
Sanford, ACS Catal. 2013, 3, 2412; e) G. A. Filonenko, M. P. Conley, C.
Copꢀret, M. Lutz, E. J. M. Hensen, E. A. Pidko, ACS Catal. 2013, 3,
2522; f) G. A. Filonenko, D. Smykowski, B. M. Szyja, G. Li, J. Szczygieł,
E. J. M. Hensen, E. A. Pidko, ACS Catal. 2015, 5, 1145; g) A. J.
Kosanovich, C. H. Komatsu, N. Bhuvanesh, L. M. Pérez, O. V. Ozerov,
Chem. Eur. J. 2018, 24, 13754.
reservoir for an unconventional 16-e NHC-phosphonium ylide
complex able to activate H2 through a metal-ligand cooperation
mode based on the formal interplay between 5- and 3-P
species. Homogeneous catalysis can take advantage of this new
mode of H2 activation, as demonstrated by the development of
one of the most efficient Mn-based catalytic systems for
hydrogenation of ketones. Taking into account the ubiquitous
presence of the ‘R2PCH2’ motif in transition metal complexes, an
awareness of its potential as a non-innocent ligand could now
open new perspectives in homogeneous catalysis.
Acknowledgements
We thank the CNRS and the IUF (France) for general support of
this project. R. B. is grateful to the Embassy of Yemen in Paris
for a PhD fellowship. Computational studies were performed
using HPC resources from CALMIP (Grant no. P18038).
[15] Related adducts of dearomatized pincer complexes with nitriles: a) G. A.
Filonenko, E. Cosimi, L. Lefort, M. P. Conley, C. Copꢀret, M. Lutz, E. J.
M. Hensen, E. A. Pidko, ACS Catal. 2014, 4, 2667; b) S. Perdriau, D. S.
Zijlstra, H. J. Heeres, J. G. de Vries, E. Otten, Angew. Chem. Int Ed.
2015, 54, 4236, Angew. Chem. 2015, 127, 4310; c) L. E. Eijsink, S. C.
P. Perdriau, J. G. de Vries, E. Otten, Dalton Trans. 2016, 45, 16033; d)
A. Nerush, M. Vogt, U. Gellrich, G. Leitus, Y. Ben-David, D. Milstein, J.
Am. Chem. Soc. 2016, 138, 6985.
[16] Similar Mn(I) complexes [(κ2P,C-R2P–C(H)R’)Mn(CO)4]: a) E. Lindner,
K. A. Starz, H.-J. Eberle, W. Hiller, Chem. Ber. 1983, 116, 1209; b) G.
D. Vaughn, K. A. Krein, J. A. Gladysz, Organometallics 1986, 5, 936; c)
E. Lindner, E. Ossig, M. Darmuth, J. Organomet. Chem. 1989, 379, 107.
[17] Related complexes with chelating methanide ligands: a) M. Devillard, C.
Alvarez Lamsfus, V. Vreeken, L. Maron, J. I. van der Vlugt, Dalton
Trans. 2016, 45, 10989; b) T. Simler, G. Frison, P. Braunstein, A. A.
Danopoulos, Dalton Trans. 2016, 45, 2800; c) S. Chakraborty, U.
Gellrich, Y. Diskin-Posner, G. Leitus, L. Avram, D. Milstein, Angew.
Chem. Int Ed. 2017, 56, 4229; Angew. Chem. 2017, 129, 4293; M.
Devillard, A. Ehlers, M. A. Siegler, J. I. van der Vlugt, Chem. Eur. J.
2019 DOI: 10.1002/chem.201805504.
Keywords: Metal-ligand cooperation • Phosphonium ylides •
N-heterocyclic carbenes • Manganese • DFT calculations
[1]
a) B. L. Conley, M. K. Pennington-Boggio, E. Boz, T. J. Williams, Chem.
Rev. 2010, 110, 2294; b) A. Quintard, J. Rodriguez, Angew. Chem. Int.
Ed. 2014, 53, 4044; Angew. Chem. 2014, 126, 4124.
[2]
[3]
[4]
J. R. Khusnutdinova, D. Milstein, Angew. Chem. Int. Ed. 2015, 54,
12236; Angew. Chem. 2015, 127, 12406.
D. W. Stephan, G. Erker, Angew. Chem. Int. Ed. 2015, 54, 6400;
Angew. Chem. 2015, 127, 6498.
a) E. von Grotthuss, M. Diefenbach, M. Bolte, H.-W. Lerner, M. C.
Holthausen, M. Wagner, Angew. Chem. Int. Ed. 2016, 55, 14067;
Angew. Chem. 2016, 128, 14273; b) J. W. Taylor, A. McSkimming, C. F.
Guzman, W. H. Harman, J. Am. Chem. Soc. 2017, 139, 11032.
a) Handbook of Homogeneous Hydrogenation (Eds. J. G. de Vries, C. J.
Elsevier), Wiley-VCH, Weinheim, 2007; b) D. Wang, D. Astruc, Chem.
Rev. 2015, 115, 6621; c) C. Gunanathan, D. Milstein, Chem. Rev. 2014,
114, 12024.
[5]
[18] Y. Nakajima, F. Ozawa, Organometallics 2012, 31, 2009.
[19] a) Y. Canac, C. Lepetit, M. Abdalilah, C. Duhayon, R. Chauvin, J. Am. Chem.
Soc. 2008, 130, 8406; b) I. Benaissa, R. Taakili, N. Lugan, Y. Canac, Dalton
Trans. 2017, 46, 12293; c) C. Barthes, C. Bijani, N. Lugan, Y. Canac, Y.
Organometallics 2018, 37, 673; d) R. Taakili, C. Lepetit, C. Duhayon, D. A.
Valyaev, N. Lugan, Y. Canac, Dalton. Trans. 2019, 48, 1709.
[6]
[7]
a) A. Corma, J. Navas, M. J. Sabater, Chem. Rev. 2018, 118, 1410; b) T.
Irrgang, R. Kempe, Chem. Rev. 2018, DOI: 10.1021/acs.chemrev.8b00306.
a) T. Ikariya, A. J. Blacker, Acc. Chem. Res. 2007, 40, 1300; b) R.
Noyori, T. Ohkuma, Angew. Chem. Int. Ed. 2001, 40, 40; Angew. Chem.
2001, 113, 40.
[20] C. H. Leung, C. D. Incarvito, R. H. Crabtree, Organometallics 2006, 25, 6099.
[21] G. Sipos, A. Ou, B. W. Skelton, L. Falivene, L. Cavallo, R. Dorta, Chem.
Eur. J. 2016, 22, 6939.
[8]
a) A. M. Poitras, S. E. Knight, M. W. Bezpalko, B. M. Foxman, C. M.
Thomas, Angew. Chem. Int. Ed. 2018, 57, 1497; Angew. Chem. 2018,
130, 1513; b) M. Xu, A. R. Jupp, Z.-W. Qu, D. W. Stephan, Angew.
Chem. Int. Ed. 2018, 57, 11050; Angew. Chem. 2018, 130, 11216; c) A.
T. Normand, C. G. Daniliuc, B. Wibbeling, G. Kehr, P. Le Gendre, G.
Erker, J. Am. Chem. Soc. 2015, 137, 10796; d) E. J. Derrah, D. A.
Pantazis, R. McDonald, L. Rosenberg, Organometallics 2007, 26, 1473;
e) M. D. Fryzuk, K. Bhangu, J. Am. Chem. Soc. 1988, 110, 961; f) N.
Lugan, G. Lavigne, J.-J. Bonnet, R. Réau, D. Neibecker, I. Tkatchenko,
J. Am. Chem. Soc. 1988, 110, 5369.
[22] Other η2-H2 Mn(I) complexes evidenced by DFT calculations: a) C. Liu,
R. van Putten, P. O. Kulyaev, G. A. Filonenko, E. A. Pidko, J. Catal.
2018, 363, 136; b) R. van Putten, E. A. Uslamin, M. Garbe, C. Liu, A.
Gonzalez-de-Castro, M. Lutz, K. Junge, E. J. M. Hensen, M. Beller, L.
Lefort, E. A. Pidko, Angew. Chem. Int. Ed. 2017, 56, 7531; Angew.
Chem. 2017, 129, 7639; c) E. B. Hulley, M. L. Helm, R. M. Bullock,
Chem. Sci. 2014, 5, 4729.
[23] a) S. Elangovan, C. Topf, S. Fischer, H. Jiao, A. Spannenberg, W.
Baumann, R. Ludwig, K. Junge, M. Beller, J. Am. Chem. Soc. 2016, 136,
8809; b) F. Kallmeier, T. Irrgang, T. Dietel, R. Kempe, Angew. Chem. Int.
Ed. 2016, 55, 11806; Angew. Chem. 2016, 128, 11984; c) M. B. Widegren,
G. J. Harkness, A. M. Z. Slawin, D. B. Cordes, M. L. Clarke, Angew.
Chem. Int. Ed. 2017, 56, 5825; Angew. Chem. 2017, 129, 5919; d) S.
Weber, B. Stöger, K. Kirchner, Org. Lett. 2018, 20, 7212.
[9]
a) C. Gunanathan, D. Milstein, Acc. Chem. Res. 2011, 44, 588; b) L. Alig,
M. Fritz, S. Schneider, Chem. Rev. 2018 10.1021/acs.chemrev.8b00555
[10] a) A. Bruneau-Voisine, D. Wang, T. Roisnel, C. Darcel, J.-B. Sortais,
Catal. Commun. 2017, 92, 1; b) A. Bruneau-Voisine, D. Wang, V.
Dorcet, T. Roisnel, C. Darcel, J.-B. Sortais, Org. Lett. 2017, 19, 3656;
b) D. Wang, A. Bruneau-Voisine, J.-B. Sortais, Catal. Commun. 2018,
105, 31; c) D. Wei, A. Bruneau-Voisine, T. Chauvin, V. Dorcet, T.
[24] P. A. Dub, J. C. Gordon, ACS Catal. 2017, 7, 6635.
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10.1002/anie.201901169
Angewandte Chemie International Edition
COMMUNICATION
Entry for the Table of Contents
COMMUNICATION
R. Buhaibeh, O. A. Filippov, A. Bruneau-
Voisine, J. Willot, C. Duhayon, D. A.
Valyaev,* N. Lugan,* Y. Canac* and
J.-B. Sortais*
Page No. – Page No.
Phosphine-NHC Manganese
Hydrogenation Catalyst Exhibiting a
Non-Classical Metal-Ligand
A NHC-phosphine manganese complex in the presence of base is transformed into a
NHC-phosphinomethanide derivative capable to easily activate dihydrogen via a non-
classical metal-ligand cooperative mode. This process is relevant for catalysis providing
one of the most efficient Mn-based systems for ketone hydrogenation.
Cooperative H2 Activation Mode
This article is protected by copyright. All rights reserved.