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Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
NHC-manganese(i) complexes as carbene transfer agents.
Javier Ruiz1, Angela Berros, Bernabé F Perandones
1Departamento de Química Orgánica e Inorgánica, Facultad de Química, Universidad de Oviedo, 33006, Oviedo, Spain. jruiz@uniovi.es
Dalton Transactions (Cambridge, England : 2003)
|May 8, 2010
Summary
This study demonstrates the tautomerization of azoles to N-heterocyclic carbenes (NHCs) in manganese complexes. These NHC-manganese complexes act as carbene transfer agents to gold, forming heterometallic intermediates.
Area of Science:
- Organometallic Chemistry
- Coordination Chemistry
- Catalysis
Background:
- Azoles are versatile ligands in coordination chemistry.
- N-heterocyclic carbenes (NHCs) are important ligands with unique electronic properties.
- Manganese complexes can serve as precursors for NHC ligands.
Purpose of the Study:
- To synthesize N-heterocyclic carbene (NHC) manganese(I) complexes.
- To investigate the carbene transfer capabilities of these NHC-manganese complexes.
- To explore the reactivity of NHC-manganese complexes with gold and silver fragments.
Main Methods:
- Reaction of manganese complexes with KO(t)Bu for tautomerization.
- Protonation of intermediates to form NHC-manganese complexes.
- Carbene transfer reactions using NHC-manganese complexes with gold and silver precursors.
Main Results:
- Successful synthesis of NHC-manganese(I) complexes.
- Demonstration of carbene transfer from manganese to gold, forming heterometallic intermediates.
- Observation of inverse tautomerization with silver(I) fragments, preventing carbene transfer.
Conclusions:
- NHC-manganese complexes are effective carbene transfer agents to gold.
- The reactivity with silver differs, leading to inverse tautomerization.
- This study expands the understanding of carbene transfer mechanisms and heterometallic complex synthesis.
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