In the last decade, organocatalysis, the use of small chiral organic molecules as catalysts, has proven to be a valuable and attractive tool for the synthesis of enantiomerically enriched molecules. A number of organocatalysts and processes, such as one-pot, tandem, cascade or multicomponent reactions, have been reported to date. Furthermore, the many advantages of organocatalysis - robust, non-toxic, affordable, inert atmosphere, easy reaction manipulation, etc. - allow the preparation of bioactive compounds using simple and metal-free procedures, thus avoiding false positives in the biological evaluation. This mini-review focuses on medicinal chemistry programs that have synthesized biologically active compounds using one or more organocatalytic steps. In this respect, the potential of organocatalytic methods for enabling the chemical synthesis of important medicinal targets will be highlighted.

The catalyst system formed by Cu(CH3CN)4ClO4 and the planar chiral P,S-ligand Fesulphos behaves as a very efficient chiral Lewis acid in the catalytic asymmetric 1,3-dipolar cycloaddition of azomethine ylides. This catalyst shows a remarkable reactivity at low catalyst loading (0.5-3 mol %), affording in good yields the endo adducts with exceptional levels of enantioselectivity (up to >99% ee). This catalytic asymmetric procedure has a broad structural scope with regard to both azomethine and dipolarophile substitution. The first examples of catalytic asymmetric 1,3-dipolar cycloaddition with ketimine-derived azomethines are reported.

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Quinone pro quo: The organocatalytic enantioselective α‐arylation of aldehydes using quinones as the aromatic partner was carried out. The reaction proceeds well using H2O or EtOH/H2O mixtures as solvent. The corresponding optically active α‐arylated aldehydes are obtained in high yields and with excellent enantioselectivities (see scheme; TMS: trimethylsilyl).