Bottleable NiCl2(dppe) as a catalyst for the Markovnikov-selective hydroboration of styrenes with bis(pinacolato)diboron

Article abstract of DOI:10.1039/d0cc05246a

Although transition-metal-catalysed hydroboration reactions of alkenes have been extensively studied, only three examples using Ni complexes have been reported so far. In this study, we have examined hydroboration reactions of alkenes using Ni/phosphine complexes. The commercially available and bottleable complex NiCl2(dppe) (dppe = 1,2-bis(diphenylphosphino)ethane) serves as a catalyst for the highly Markovnikov-selective hydroboration of styrene derivatives that affords the desired Markovnikov products in high yield.

Full text of DOI:10.1039/d0cc05246a

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Bottleable NiCl2(dppe) as a catalyst for the Markovnikov-selective
hydroboration of styrenes with bis(pinacolato)diboron
Toru Hashimoto,* Toshiya Ishimaru, Keisuke Shiota, and Yoshitaka Yamaguchi*
Received 00th January 20xx,
Accepted 00th January 20xx
DOI: 10.1039/x0xx00000x
Albeit that transition-metal-catalysed hydroboration reactions of hydroboration of alkenes remains limited.8 In 2016, Schomaker
alkenes have been extensively studied, only three examples using reported a heteroleptic nickel complex with both N-heterocyclic
Ni complexes have been reported so far. In this study, we have
examined hydroboration reactions of alkenes using Ni/phosphine
N
N
Ar
Ar
O
Ni
O
O
Ph
Ph
Ph
Ph
complexes. The commercially available and bottleable complex
NiCl2(dppe) (dppe = 1,2-bis(diphenylphosphino)ethane) serves as a
catalyst for the highly Markovnikov-selective hydroboration of
styrene derivatives that affords the desired Markovnikov products
in high yield.
O
O
O
O
P
P
N
Ni Cl
Ni
Cl Ni Cl
PCy3
Cl
Cl
PPh2
NiCl2(PCy3)(NHC)
Ni(PLY)2(THF)2
1
NiCl2(dppe)
This work
Schomaker 2016
Mandal 2019
Our group 2020
Fig. 1 Ni complexes for Markovnikov-selective hydroboration reactions.
Hydroboration reactions of alkenes are of great academic
and industrial importance as a key step in the synthesis of
boron-containing compounds and, accordingly, have been
explored extensively.1,2 Transition-metal-catalysed alkene
hydroboration reactions have obvious advantages such as high
chemo- and regioselectivity and broad functional-group
compatibility. Catalysts based on precious metals such as Rh
and Ir are most widely applied in hydroboration reactions due
to their high activity and selectivity.3 However, the economic
and environmental concerns associated with these catalysts
have led to considerable interest in replacing them with
catalysts based on earth-abundant first-row transition metals.4
Over the past decade, great progress has been made in the
development of Cu-catalysed alkene hydroboration reactions.5
The use of Fe- and Co-based catalysts has also attracted
considerable attention recently owing to their unique reactivity
and reaction mechanism.6,7 The use of these metals in
combination with multidentate ligands has led to tremendous
advances in the Markovnikov-selective hydroboration of
alkenes. Despite the excellent results achieved using Cu, Fe, and
Co catalysts, the use of Ni catalysts in the Markovnikov-selective
carbene (NHC) and tricyclohexylphosphine (PCy3) ligands that
showed high Markovnikov selectivity for the hydroboration of
styrene derivatives using pinacolborane (HBPin) (Fig. 1).8a
A
nickel complex bearing a phenalenyl-based ligand (PLY) was
used as an effective catalyst for alkene hydroboration.8b Very
recently, we have reported that the -aminoketonato-based
O,N,P-pincer-type nickel complex 1 effectively catalyses the
highly Markovnikov-selective hydroboration of styrene
derivatives using bis(pinacolato)diboron (B2pin2).8c,9 However,
the synthesis of these nickel complexes is laborious, and their
sensitivity to air and moisture requires storage under inert
atmospheres. These drawbacks led us to investigate more
accessible and more robust Ni complexes that effectively
catalyse the hydroboration of alkenes. We focused on
Ni/phosphine complexes, as many Ni/phosphine complexes are
commercially available or easily synthesised, and they often
show desirable stability toward air and moisture. We found that
a Ni complex that bears a suitable bidentate phosphine ligand
can serve as an efficient catalyst for the Markovnikov-selective
hydroboration of styrene derivatives.
Initially, we attempted the hydroboration of 4-
methoxystyrene (2a) using a variety of phosphine-ligated Ni
complexes under our previously reported reaction conditions
(Table 1).8c,10 Treatment of 2a with B2pin2 (3, 2.0 equiv) in the
presence of the O,N,P-coordinated nickel complex 1 as a
catalyst (5 mol%) and KOAc as a base (2.0 equiv) in
toluene/MeOH (3:1, v/v) at 25 °C afforded the corresponding
a. Department of Advanced Materials Chemistry, Graduate School of Engineering,
Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-
8501, Japan. E-mail: hashimoto-toru-kh@ynu.ac.jp, yamaguchi-yoshitaka-
hw@ynu.ac.jp
† Electronic Supplementary Information (ESI) available. See
DOI: 10.1039/x0xx00000x
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DOI: 10.1039/D0CC05246A
Table 1 Optimisation of the reaction conditionsa
Ni cat. (5.0 mol%)
BPin
BPin
3 (2.0 equiv)
BPin
BPin
Base (2.0 equiv)
+
+
+
toluene/MeOH (3:1, v/v)
25 ºC, 24 h
MeO
MeO
MeO
MeO
MeO
2a
4a
5a
6a
7a
Yield 4a
Yield 5a
Yield 6a
Yield 7a
Recovery of
Entry
Ni cat.
Base
(%)b
58
49
55
97
84
86
80
0
(%)b
<1
6
(%)b
0
(%)c
5
2a (%)c
25
37
28
0
1
2
3
4
5
6
7
8
1
KOAc
KOAc
KOAc
KOAc
KOAc
KOAc
NaOAc
KOt-Bu
NaOMe
KOAc
–
NiCl2(PPh3)2
NiCl2(PCy3)2
NiCl2(dppe)
NiCl2(dppp)
NiCl2(dppf)
NiCl2(dppe)
NiCl2(dppe)
NiCl2(dppe)
NiCl2(dppe)
NiCl2(dppe)
–
0
0
0
0
0
0
4
92
0
6
0
0
5
17
0
0
0
0
11
0
0
0
0
11
0
8
0
0
97
85
63
0
10
76
0
0
0
9
0
0
0
0
10d
11
12
0
35
KOAc
0
a Reaction conditions: 2a (0.50 mmol), 3 (1.00 mmol), nickel catalyst (5 mol%), base (1.00 mmol), toluene (3 mL), MeOH (1 mL), 25 °C, 24 h. b Determined by NMR analysis
using an internal standard. c Determined by GC analysis using an internal standard. d Without MeOH.
product (4a) in 58% yield with high Markovnikov selectivity;
25% of the 2a could be recovered (entry 1). To improve the yield
Table 2 Hydroboration of styrene derivatives 2a
of 4a, we examined other nickel sources (entries 2–6). Ni
NiCl2(dppe) (5.0 mol%)
OH
3 (2.0 equiv)
R
R
R
OH
complexes that bear monodentate phosphine ligands, such as
NiCl2(PPh3)2 and NiCl2(PCy3)2, were not effective for the
hydroboration of 2a, providing 4a in merely moderate yield
(entries 2 and 3). In contrast, Ni complexes that bear bidentate
phosphine ligands, such as 1,2-bis(diphenylphosphino)ethane
(dppe), 1,3-bis(diphenylphosphino)propane (dppp), or 1,1′-
bis(diphenylphosphino)ferrocene (dppf) afforded 4a in good-
to-high yield with high Markovnikov selectivity (entries 4–6).
Among these complexes, NiCl2(dppe) showed the best
performance, affording 4a in 97% yield with high Markovnikov
selectivity (entry 4). Using NiCl2(dppe) as the catalyst, we then
explored different bases. When NaOAc was used, the yield of 4a
decreased to 80% (entry 7). KOt-Bu did not afford 4a, while
forming 5a in 11% yield and 4-ethylanisole (7a) in 76% yield
(entry 8). In the case of NaOMe, 4a was not formed (entry 9).10
When MeOH was removed from the reaction system, 4a was
not formed, and 2a was recovered almost quantitatively (97%)
(entry 10). Reactions without KOAc or NiCl2(dppe) also did not
afford 4a (entries 11 and 12).
KOAc (2.0 equiv)
+
toluene/MeOH (3:1, v/v)
25 ºC, 24 h
2
8
9
then, H2O2, NaOH aq.
OH
OH
OH
OH
t-Bu
Ph
8b, 84%
8c, 89%
8d, 86%
8e, 73%
OH
OH
OH
OH
TBSO
BnO
F
8f, 75%
8g, 53%
8h, 41%b
8i, 70%
OH
OH
OH
8j, 63%
8k, 83%
8l, 88%
With the optimized reaction conditions in hand, we
examined the substrate scope using various styrene derivatives
(2), and the corresponding products (4) were isolated after
oxidation into the respective secondary alcohols (8) (Table 2).
The reaction using styrene (2b) afforded 8b in 84% isolated yield.
Styrene derivatives with a methyl (2c), t-butyl (2d), or phenyl
(2e) substituent at the 4-position showed good reactivity and
Markovnikov selectivity, and were converted into benzyl
alcohols 8c–8e in 73–89% yield. Various functionalities, such as
a Reaction conditions: 2a (0.50 mmol), 3 (1.00 mmol), NiCl2(dppe) (5 mol%), KOAc
(1.00 mmol), toluene (3 mL), MeOH (1 mL), 25 ºC, 24 h. Isolated yield. b The reaction
was performed using 10 mol% of NiCl2(dppe).
siloxy (2f), benzyloxy (2g), and fluoro (2h) groups, were
tolerated under the present reaction conditions, and the
corresponding alcohols (8f–8h) were formed in 41–75% yield.
When the sterically demanding 2-methylstyrene (2i) and 2,4,6-
trimethylstyrene (2j) were used, the reactions proceeded
smoothly to afford the desired products (8i and 8j) in good yield.
2 | J. Name., 2012, 00, 1-3
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1-Vinyl- (2k) and 2-vinylnaphthalene (2l) afforded 8k and 8l in
83% and 88% yield, respectively. In all cases, the corresponding
primary alcohols (9) and diborylated product (6) were not
detected, while hydrogenated products (7) were formed as
major by-products.
Next, we examined the hydroboration reaction of - and -
substituted styrene derivatives (10, 13, and 15) with 3 using 10
mol% NiCl2(dppe) as the catalyst (Scheme 1). The reaction with
1,1-diphenylethylene (10) was carried out at 80 °C for 24 h,
albeit that the borylated products 11 and 12 were not formed,
and 10 was recovered in 73%. In the case of trans-stilbene (13),
the hydroboration reaction (48 h at 25 °C) followed by an
oxidation reaction furnished 14 in 85% yield. Under the same
reaction conditions, cis-stilbene (15) was also converted into 14
in 81% yield. - or -Alkyl-substituted styrenes and aliphatic
terminal and internal alkenes did not react under the applied
reaction conditions.
R
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DOI: 10.1039/D0CC05246A
P
P
OMe
NiII
H
2
MeOH
B
P
3
P
OMe
OMe
P
P
Cl
NiII
Cl
P
Ni0
P
NiII
KOAc
NiII
P
P
R
R
H
H
A
P = PPh2
C
C'
BPin
P
BPin
3
R
NiII
P
KOAc
R
H
4
AcOBPin
KOMe
D
Scheme 3 Proposed reaction mechanism for NiCl2(dppe)-catalysed Markovnikov-
selective hydroboration of styrene derivatives (2) with bis(pinacolato)diboron (3)
hydroboration product 4 under concomitant regeneration of
the active nickel (0) species A.15,16
NiCl2(dppe) (10 mol%)
In summary, we have developed a NiCl2(dppe)-catalysed
reaction for the hydroboration of styrene derivatives with
B2pin2 in toluene/MeOH. The air- and moisture-stable and
commercially available complex NiCl2(dppe) effectively
catalyses the hydroboration of styrene derivatives with high
Markovnikov selectivity. The reactions proceed smoothly under
very mild reaction conditions to afford the products in good-to-
high yield. Further experimental and computational studies on
the reaction mechanism are currently in progress.
3 (3.0 equiv)
Ph
Ph
Ph
BPin
KOAc (3.0 equiv)
BPin
+
Ph
Ph
11, n.d.
Ph
toluene/MeOH (3:1, v/v)
80 ºC, 48 h
10
12, n.d.
NiCl2(dppe) (10 mol%)
3 (3.0 equiv)
OH
KOAc (3.0 equiv)
Ph
Ph
Ph
Ph
toluene/MeOH (3:1, v/v)
25 ºC, 48 h
13
14, 85%
then, H2O2, NaOH aq.
This work was financially supported by JSPS KAKENHI Grant
Number JP17K05805 in Grant-in-Aid for Scientific Research (C)
from MEXT (Japan), and the Collaborative Research Program of
the Institute for Chemical Research, Kyoto University (2019–
25). T.H. thanks the Collaborative Research Projects of the
Laboratory for Materials and Structures, Institute of Innovative
Research, Tokyo Institute of Technology. The authors are
grateful to Prof. Masaharu Nakamura and Dr. Katsuhiro Isozaki
(Kyoto Univ.) for their kind help with the HRMS measurements.
NiCl2(dppe) (10 mol%)
3 (3.0 equiv)
OH
KOAc (3.0 equiv)
Ph
Ph
Ph
toluene/MeOH (3:1, v/v)
25 ºC, 48 h
Ph
15
14, 81%
then, H2O2, NaOH aq.
Scheme 1 Hydroboration of 10, 13, and 15.
To obtain mechanistic insight into this alkene hydroboration
reaction, an isotope-labelling experiment was carried out
(Scheme 2). When MeOD-d1 was used instead of MeOH, alcohol
8a-D was formed in 90% yield with 92% deuteration of one
hydrogen atom on the methyl group. On the basis of this result
Conflicts of interest
There are no conflicts to declare.
NiCl2(dppe) (5.0 mol%)
OH
3 (2.0 equiv)
D
KOAc (2.0 equiv)
92% D
toluene/MeOD-d1 (3:1, v/v)
Notes and references
MeO
MeO
25 ºC, 24 h
2a
8a-D, 90%
1
Boronic Acids: Preparation and Applications in Organic
Synthesis, Medicine and Materials, 2nd revised, ed., Hall, D.
G., Ed., Wiley- VCH: Weinheim, 2011.
(a) D. Leonori and V. K. Aggarwal, Acc. Chem. Res., 2014, 47,
3174. (b) D. Leonori and V. K. Aggarwal, Angew. Chem., Int.
Ed., 2015, 54, 1082. (c) K. Fagnou and M. Lautens, Chem. Rev.,
2003, 103, 169. (d) N. Miyaura and A. Suzuki, Chem. Rev.,
1995, 95, 2457. (e) R. Jana, T. P. Pathak and M. S. Sigman,
Chem. Rev., 2011, 111, 1417.
then, H2O2, NaOH aq.
Scheme 2 Isotope-labelling experiment
2
and of previous reports,8a,11,12 we propose a possible reaction
mechanism shown in Scheme 3. Initially, Ni(0) species A is
generated by the reduction of 3 with NiCl2(dppe) in the
presence of KOAc.8a,13 Subsequently, the oxidative addition of
the O–H bond of MeOH to Ni(0) species A affords methoxy Ni(II)
hydride B.11 The hydride of B is transferred to the terminal
carbon atom of the double bond of styrene 2 to form benzyl
nickel intermediates C and C′, which might be in equilibrium. At
this point, we assume that the nickel intermediate C would be
favoured relative to C′.14 Finally, C undergoes transmetalation
with 3, followed by a reductive elimination of D to generate the
3
4
For reviews on precious-metal-catalysed hydroboration
reactions, see: (a) K. Burgess and M. J. Ohlmeyer, Chem. Rev.,
1991, 91, 1179. (b) I. Beletskaya and A. Pelter, Tetrahedron,
1997, 53, 4957. (c) C. M. Crudden and D. Edwards, Eur. J. Org.
Chem., 2003, 4695. (d) A.-M. Carroll, T. P. O’Sullivan and P. J.
Guiry, Adv. Synth. Catal., 2005, 347, 609.
For
reviews
on
first-row-transition-metal-catalysed
hydroboration reactions, see: (e) J. A. Schiffner, K. Müther and
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 3
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Journal Name
M. Oestreich, Angew. Chem., Int. Ed., 2010, 49, 1194. (f) J. A.
Bull, Angew. Chem., Int. Ed., 2012, 51, 8930. (g) W. Fan, L. Li
and G. Zhang, J. Org. Chem., 2019, 84, 5987.
For hydroboration reactions using Cu catalysts, see: (a) D.
Noh, H. Chea, J. Ju and J. Yun, Angew. Chem., Int. Ed., 2009,
The following regioselective addition of Ni-B species to a
styrene derivative affords theDOI:c1o0r.r1e0s3Vp9i/oeDwn0AdCritCnicg0le5O2n4l6inAe-
borylalkylnickel species. Protonation of the Ni-C bond in the
-borylalkylnickel species then produces the desired product.
For details, see ref. 8c.
5
6
7
48, 6062. (b) R. Corberán, N. W. Mszar and A. H. Hoveyda, 16 The choice of the alcohols is critical for the present reaction.
Angew. Chem., Int. Ed., 2011, 50, 7079. (c) Y. Wen, J. Xie, C.
Deng and C. Li, J. Org. Chem., 2015, 80, 4142. (d) H. Iwamoto,
K. Kubota and H. Ito, Chem. Commun., 2016, 52, 5916. (e) H.
A. Kerchner and J. Montgomery, Org. Lett., 2016, 18, 5760. (f)
Y. Xi and J. F. Hartwig, J. Am. Chem. Soc. 2016, 138, 6703.
For hydroboration reactions using Fe catalysts, see: (a) J. V.
Obligacion and P. J. Chirik, Org. Lett., 2013, 15, 2680. (b) L.
Zhang, D. Peng, X. Leng and Z. Huang, Angew. Chem., Int. Ed.,
2013, 52, 3676. (c) K.-N. T. Tseng, J. W. Kampf and N. K.
Szymczak, ACS Catal., 2015, 5, 411. (d) A. J. MacNair, C. R. P.
Millet, G. S. Nichol, A. Ironmonger and S. P. Thomas, ACS
Catal., 2016, 6, 7217. (e) X. Chen, Z. Cheng and Z. Lu, Org. Lett.,
2017, 19, 969.
For hydroboration reactions using Co catalysts, see: (a) M. L.
Scheuermann, E. J. Johnson and P. J. Chirik, Org. Lett., 2015,
17, 2716. (b) W. N. Palmer, T. Diao, I. Pappas and P. J. Chirik,
ACS Catal., 2015, 5, 622. (c) S. W. Reilly, C. E. Webster, T. K.
Hollis and H. U. Valle, Dalton Trans. 2016, 45, 2823. (d) J. Peng,
J. H. Docherty, A. P. Dominey and S. P. Thomas, Chem.
Commun., 2017, 53, 4726. (e) S. R. Tamang, D. Bedi, S. Shafiei-
Haghighi, C. R. Smith, C. Crawford and M. Findlater, Org. Lett.,
2018, 20, 6695. (f) P. K. Verma, A. S. Sethulekshmi and K.
Geetharani, Org. Lett., 2018, 20, 7840. (g) G. Zhang, J. Wu, S.
Li, S. Cass and S. Zheng, Org. Lett., 2018, 20, 7893. (h) X. Chen,
Z. Cheng and Z. Lu, ACS Catal., 2019, 9, 4025.
The reaction using EtOH instead of MeOH proceeded very
slowly (54% conversion) to give the targeted product in 48%
yield. Moreover, i-PrOH furnished only 15% of the desired
product, while t-BuOH did not afforded any product. For
details, see the ESI.
8
9
For Markovnikov-selective hydroboration reactions using Ni
catalysts, see: (a) E. E. Touney, R. Van Hoveln, C. T. Buttke, M.
D. Freidberg, I. A. Guzei and J. M. Schomaker,
Organometallics, 2016, 35, 3436. (b) G. Vijiaykumar, M.
Bhunia and S. K. Mandal, Dalton Trans. 2019, 48, 5779. (c) T.
Hashimoto, K. Shiota and Y. Yamaguchi, Org. Lett., 2020, 22,
4033.
(a) E. Asano, Y. Hatayama, N. Kurisu, A. Ohtani, T. Hashimoto,
Y. Kurihara, K. Ueda, S. Ishihara, H. Nagao and Y. Yamaguchi,
Dalton Trans., 2018, 47, 8003. (b) N. Kurisu, E. Asano, Y.
Hatayama, Y. Kurihara, T. Hashimoto, K. Funatsu, K. Ueda and
Y. Yamaguchi, Eur. J. Inorg. Chem., 2019, 126. (c) T.
Hashimoto, K. Funatsu, A. Ohtani, E. Asano and Y. Yamaguchi,
Molecules, 2019, 24, 2296.
10 (a) A. Bonet, C. Pubill-Ulldemolins, C. Bo, H. Gulyás and E.
Fernández, Angew. Chem., Int. Ed., 2011, 50, 7158. (b) N.
Miralles, J. Cid, A. B. Cuenca, J. J. Carbó and E. Fernández,
Chem. Commun., 2015, 51, 1693.
11 (a) L.-J. Xiao, L. Cheng, W.-M. Feng, M.-L. Li, J.-H. Xie and Q.-L.
Zhou, Angew. Chem., Int. Ed., 2018, 57, 461. (b) M. Gaydou, T.
Moragas and F. Juliá-Hernández, R. Martin, J. Am. Chem. Soc.
2017, 139, 12161. (c) L. González-Sebastián, M. Flores-Alamo
and J. J. García, Organometallics, 2012, 31, 8200.
12 J. Huang, W. Yan, C. Tan, W. Wu and H. Jiang, Chem. Commun.,
2018, 54, 1770.
13 For details, see the ESI.
14 For examples of the isolation and characterisation of benzyl
nickel species, see: (a) E. Carmona, J. M. Marín, M. Paneque
and M. L. Poveda, Organometallics 1987, 6, 1757. (b) E.
Carmona, M. Paneque and M. L. Poveda, Polyhedron 1989, 8,
285. (c) J. R. Ascenso, M. A. A. F. de C. T. Carrondo, A. R. Dias,
P. T. Gomes, M. Fátima, M. Piedade, C. C. Romao, A. Revillon
and I. Tkatchenko, Polyhedron 1989, 8, 2449. (d) I. Albers, E.
Álvarez, J. Cámpora, C. M. Maya, P. Palma, L. J. Sánchez and E.
Passaglia, J. Organomet. Chem. 2004, 689, 833.
15 An alternative reaction mechanism could be considered:
NiCl2(dppe) reacts with 3 and KOAc to generate Ni-B species.
4 | J. Name., 2012, 00, 1-3
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