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Ar
NN
Ph
Ph
N
PhS
S
S
N
Ar
Pd
Pd
Pd
Ar
PhS
Pd SPh
N
N
S
S
SPh
N
Ph
Ph
Ar
103
104
Figure 4.43
[Pd(NHC)] species involved in the catalytic cycle.
Complex 103 was found to be active under the reaction conditions whereas
104 was not, unless extra additives were added (6% pyridine or 2 equiv. of
KOEt) to break the aggregate.
4.4 Conclusion
We have attempted to demonstrate that much has been done with the NHC
ligand class in palladium cross-coupling catalysis. It is clear that the winners
of the 2010 Nobel Prize in Chemistry laid the groundwork for these latest
developments and the research community is immensely indebted to them
for their still inspiring contributions. The work in this area continues to
generate fascinating surprises in terms of catalyst reactivity and productivity.
We expect that more is to come and look forward to more exciting
developments.
References
1. (a) A. de Meijere and F. Diederich (eds), Metal-Catalysed Cross-Coupling
Reactions, Wiley-VCH, Weinheim, 2nd edn, 2004; (b) themed collection:
cross-coupling reactions in organic synthesis, Chem. Soc. Rev., 2011,
40, (10), 4877; (c) C. C. C. Johansson Seechurn, M. O. Kitching,
T. J. Colacot and V. Snieckus, Angew. Chem. Int. Ed., 2012, 51, 5062;
(d) H. Li, C. C. C. Johansson Seechurn and T. J. Colacot, ACS Catal.,
2012, 2, 1147.
2. K. C. Nicolaou, P. G. Bulger and D. Sarlah, Angew. Chem. Int. Ed., 2005,
44, 4442.
3. J.-P. Corbet and G. Mignani, Chem. Rev., 2006, 106, 2651.
4. A. Suzuki, Angew. Chem. Int. Ed., 2011, 50, 6722.
5. E.-i. Negishi, Angew. Chem. Int. Ed., 2011, 50, 6738.
6. R. F. Heck, Acc. Chem. Res., 1979, 12, 146.
7. (a) G. C. Fu, Acc. Chem. Res., 2008, 41, 1555; (b) R. Martin and
S. L. Buchwald, Acc. Chem. Res., 2008, 41, 1461; (c) D. S. Surry and
S. L. Buchwald, Angew. Chem. Int. Ed., 2008, 47, 6338.
8. (a) W. A. Herrmann, Angew. Chem. Int. Ed., 2002, 41, 1290;
(b) S. P. Nolan (ed.), N-Heterocyclic Carbenes in Synthesis, Wiley,
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