In biological systems, hydrogen bonding is used extensively for molecular recognition, substrate binding, orientation and activation. In organocatalysis, multiple hydrogen bonding by man-made catalysts can effect remarkable accelerations and selectivities as well.
Organocatalysis offers several advantages not only with respect to its synthetic range. Among “typical” advantages of organocatalysis, in particular with respect to large-scale applications, are favorable economic data of many organocatalysts, the stability of organocatalysts as well as the potential for an efficient recovery
The results demonstrate that organocatalysis can represent a valuable tool for solutions on industrial scale also. Albeit the use of organocatalysis in industry is still limited, it can be expected that the broad variety of already developed efficient organocatalytic syntheses, in combination with further breakthroughs and new applications, will contribute to an increasing number of organocatalytic large-scale reactions in the future.
Enamine catalysis often delivers valuable chiral compounds such as alcohols, amines, aldehydes, and ketones. Many of these are normally not accessible using established reactions based on transition metal catalysts or on preformed enolates or enamines, illustrating the complimentary nature of organocatalysis and metallocatalysis.
Enamine catalysis, Brønsted acid catalysis, and iminium catalysis turn out to be powerful new strategies for organic synthesis. (...) Despite its long roots, asymmetric organocatalysis is a relatively new and explosively growing field that, without doubt, will continue to yield amazing results for some time to come.
Due to the increasing number of chiral drugs in the pipeline, asymmetric synthesis and efficient chiral separation technologies are steadily gaining in importance. Recently a third class of catalysts, besides the established enzymes and metal complexes, has been added to the tool kit of catalytic asymmetric synthesis: organocatalysts, small organic molecules in which a metal is not part of the active principle.