Selected Enantioselective Reactions Catalysed by Guanidines

Substitution reactions that generally display poor atom economy are omitted from this discussion. For example, guanidine-catalysed asymmetric fluorination or trifluoromethylation are important reactions, but fluorination and trifluorination reagents typically have high negative contributions to atom economy e.g. fluorine constitutes just 5.4% of Selectfluor s molecular weight). 

We will, if possible, also evaluate the subsequent elaboration step of these reactions. While numerous highly atom economical reactions catalysed by guanidines exist, many of these methodologies exploited the use of an 

When the free base form of guanidines were used for similar epoxidations, the reactions did not give the same high level of enantioselectivity as those catalysed by guanidinium salts. These reactions also did not utilise hydrogen 

E-factotcat includes the waste from catalyst s mthesis. 

Organocatalytic asymmetric conjugate additions are an extensively studied class of important C-C and C-X (X=N, P, S, Se) bond-formation re-actions. This category primarily consists of Michael reactions and its variants. Catalysed conjugate additions generally possesses high atom economy. The negative contribution to atom economy comes from the 

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