Carbene as organocatalyst

Marion N, Diez-Gonzalez S, Nolan SP (2007) N- Ielcrocyclic carbenes as organocatalysts. Angew Chem Int Ed 46 2988-3000 Matsumoto Y, Tomioka K (2006) C2 symmetric chiral /V-heterocyclic carbene catalyst for asymmetric intramolecular Stetter reaction. Tetrahedron Lett 47 5843-5848... 

Marion N, Diez-Gonzales S, Nolan SP (2007) N-heterocyclic carbenes as organocatalysts. Angew Chem Int Ed 46 2988-3000... 

In this context, the first attempts to employ chiral iV-heterocyclic carbenes as organocatalysts in an enantioselective reaction were carried out in the context of the benzoin condensation, which combines two molecules of an aldehyde (usually an aromatic one). The first pioneering examples were developed by Sheehan and coworkers, which were followed by several authors, highlighting the report by Enders in 2002, in which, for the first time, a highly enantioselective A -heterocyclic carbene-catalyzed benzoin condensation was reported (Scheme 6.2). As can be seen in this scheme, the general principle applied to the design of these catalysts relied on a thiazolium central unit as the precursor of... 

Direct (hetero)arylation A new tool for polymer chemists 13ACR1597. N-Heterocychc carbenes as organocatalysts and structural components in metal-free polymer synthesis 13CSR2142. 

Scheme 26.20 Metal catalysis/organocatalytic 1,4 addition sequences. 26.7 iV-HETEROCYCLIC CARBENES AS ORGANOCATALYSTS...

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