EN
Organocatalysis, where organic molecules like α-amino acids, α-hydroxy
acids, nucleic acids, carbohydrates are employed to catalyze organic
transformations such as the aldol, Mannich and Michael reactions is a
rapidly expanding field of organic synthesis. Operational simplicity, ready
availability of the catalysts, selectivity, efficiency and low cost make them
an attractive alternative to metal-mediated organic transformations.
Although organocatalysts have many attractive features, this catalytic
system also suffers from often high catalyst loading or poor solubility of the
catalyst in organic solvents. Recently, ionic liquids, PEG, montmorillonite
clays have been demonstrated to be good supports helping to overcome
the limitations mentioned. These supported systems offer accepatble
trade-offs in terms of yields and selectivity with the added advantages
of recyclability of the catalyst. This review compares various supported
and unsupported aminocatalysts mainly focusing on C-C bond forming
reactions.