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[
(IPr*)PdCl
2
(TEA)] (4c): In a vial equipped with a magnetic stir
[4] For a recent study on other effects caused by bulky NHC li-
gands, see: T. Szilvási, T. Veszprémi, ACS Catal. 2013, 3, 1984–
bar, 5 (545 mg, 0.25 mmol) was suspended in chloroform (1 mL),
and an excess of triethylamine (0.5 mL) was added. The solution
was stirred at room temperature for 2 h. The removal of the solvent
afforded a pale yellow solid, which was washed with hexane, yield
5
7
7
6
1991.
[
5] Recent books on NHCs: a) N-Heterocyclic Carbenes in Transi-
tion Metal Catalysis and Organocatalysis (Ed.: C. S. J. Cazin),
Springer, London, 2010; b) N-Heterocyclic Carbenes: From
Laboratory Curiosities to Efficient Synthetic Tools (Ed.: S.
Díez-González), RSC Catalysis Series, Cambridge, 2010; c) N-
Heterocyclic Carbenes in Transition Metal Catalysis (Ed.: F.
Glorius), Springer-Verlag, Berlin, 2007.
32 mg (89%). 1H NMR (CDCl
.5 Hz, 9 H, N(CH CH ], 2.23 (s, 6 H, p-Ar-CH
Hz, 6 H, N(CH CH ], 4.44 (s, 2 H, CH), 6.07 (s, 4 H, CHPh
.70 (m, 8 H, ArH), 6.81 (s, 4 H, ArH), 7.01 (m, 12 H, ArH), 7.25
, 300 MHz): δ = 0.95 [t, J =
), 2.77 [q, J =
),
3
2
3
)
3
3
2
3
)
3
2
13
1
(
(
(
m, 14 H, ArH), 7.48 (d, J = 6 Hz, 6 H, ArH) ppm. C{ H} NMR
CDCl , 75 MHz): δ = 9.6 [s, N(CH CH ], 21.8 (s, CH -Ar), 22.3
s, CH -ArH), 46.5 [s, N(CH CH ], 50.9 (s, CHPh ), 123.1 (s,
[6] G. Altenhoff, R. Goddard, C. W. Lehman, F. Glorius, J. Am.
Chem. Soc. 2004, 126, 15195–15201; S. Würtz, F. Glorius, Acc.
Chem. Res. 2008, 41, 1523–1533.
3
2
3
)
3
3
3
2
3
)
3
2
[
7] For recent examples, see: K. H. Hoi, J. A. Coggan, M. O. Or-
gan, Chem. Eur. J. 2013, 19, 843–845; S. Meiries, A. Chartoire,
A. M. Z. Slawin, S. P. Nolan, Organometallics 2012, 31, 3402–
NHC CH), 125.8 (s, CH aromatic), 126.0 (s, CH aromatic), 127.8
s, CH aromatic), 127.9 (s, CH aromatic), 129.3 (s, CH aromatic),
29.6 (s, CH aromatic), 130.1 (s, CH aromatic), 134.6 (s, C aro-
(
1
3409; A. Chartoire, X. Frogneux, A. Boreux, A. M. Z. Slawin,
matic), 138.3 (s, C aromatic), 142.8 (s, C aromatic), 143.7 (s, C
aromatic), 145.6 (s, C aromatic), 152.5 (s, C carbene) ppm.
C
S. P. Nolan, Organometallics 2012, 31, 6947–6951; A. Char-
toire, M. Lesieur, L. Favilene, A. M. Z. Slawin, L. Cavallo,
C. S. J. Cazin, S. P. Nolan, Chem. Eur. J. 2012, 18, 4517–4521.
75
H71Cl
2
N
3
Pd (1191.71): calcd. C 75.59, H 6.01, N 3.53; found C
7
5.45, H 6.33, N 3.44.
[8] For a comprehensive review on this concept applied to the de-
sign of monoligated NHC–Pd precatalysts, see: E. A. B.
Kantchev, C. J. O’Brien, M. G. Organ, Aldrichim. Acta 2006,
Supporting Information (see footnote on the first page of this arti-
cle): Coupling product characterization, spectroscopic and crystal-
lographic data.
39, 97–110.
[
9] M.-T. Chen, D. A. Vicic, M. L. Turner, O. Navarro, Organome-
tallics 2011, 30, 5052–5056; M.-T. Chen, D. A. Vicic, W. J.
Chain, M. L. Turner, O. Navarro, Organometallics 2011, 30,
6770–6773.
Acknowledgments
[10] G. Berthon-Gelloz, M. A. Siegler, A. L. Spek, B. Tinant,
J. N. H. Reekc, I. E. Mark ο´ , Dalton Trans. 2010, 39, 1444–
1
446.
O. N. acknowledges the National Science Foundation (NSF) for
funding the initial stages of this work (grant number CHE-
0
ment Agency (NWDA) and the Engineering and Physical Sciences
Research Council (EPSRC) for support.
[
[
11] S. J. Coles, P. A. Gale, Chem. Sci. 2012, 3, 683–689.
12] General procedure: In open air, 4c (1 mol-%), aryl halide
924324). M. L. T. acknowledges the Northwest Regional Develop-
(
1 mmol), amine (1.1 mmol), KOtBu (1.1 mmol) and anhy-
drous DME (1 mL) were added in turn into a reaction vial,
which was equipped with a magnetic stirring bar and sealed
with a screw cap fitted with a septum. The reaction mixture
was allowed to stir at room temperature, and the progression
of the reaction was monitored by gas chromatography. Once
the reaction was finished, the solution was filtered through Ce-
lite, eluted with DCM, and the filtrate was evaporated in vacuo.
The crude product was finally purified by using a Teledyne
ISCO Combi Flash RF75 purification system with Biotage
Snap KP-Sil 10 g cartridges and eluted with ethyl acetate/ pe-
troleum ether mixtures. The reported yields are the average of
two runs.
[
1] For general reviews on cross-coupling reactions, see: A. de Mei-
jere, F. Diederich (Eds.), Metal-Catalyzed Cross-Coupling Re-
actions, 2nd ed., Wiley-VCH, Weinheim, Germany, 2004; O.
Navarro, S. P. Nolan, C–C Bond Formation by Cross-Coupling,
in: Comprehensive Organometallic Chemistry III, vol. 11 (Appli-
cations II: Transition Metal Compounds in Organic Synthesis
2
2
) (Eds: R. H. Crabtree, M. P. Mingos), Elsevier, New York,
007.
[
2] For an excellent and recent review, see: H. Li, C. C. C. Johans- [13] K. J. Hodgetts, A. Kieltyka, R. Brodbeck, J. N. Tran, J. W. F.
son Seechurn, T. J. Colacot, ACS Catal. 2012, 2, 1147–1164.
3] H. Lebel, M. K. Janes, A. B. Charette, S. P. Nolan, J. Am.
Chem. Soc. 2004, 126, 5046–5047.
Wasley, A. Thurkauf, Bioorg. Med. Chem. 2001, 9, 3207–3213.
[
Received: January 20, 2014
Published Online: February 13, 2014
Eur. J. Inorg. Chem. 2014, 2200–2203
2203
© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim