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The application potential of primary amine catalysts in the context of Mannich reactions of aldehydes with ketimines is exemplified by isatin-derived ketimines and cyclic trifluoromethyl ketimines. Primary amine catalysts exhibit either unusual stereoselectivity or reactivity, which is not observable with secondary amine catalysts. Moreover, reversal of diastereofacial selectivity between primary and secondary amine catalysts is disclosed. These new reactions provide useful methods for the syntheses of chiral 3-substituted 3-amino-2-oxindoles and dihydroquinazolinones bearing a trifluoromethylated quaternary stereocenter. The synthetic utility of the reactions is demonstrated through the formal synthesis of AG-041R and DPC 083 and the total synthesis of (−)-psychotriasine. [ABSTRACT FROM AUTHOR]

Herein, we describe a selective cobalt-catalyzed chemodivergent transfer hydrogenation of nitriles to synthesize primary, secondary, and tertiary amines. The solvent effect plays a key role for the selectivity control. The general applicability of this procedure was highlighted by the synthesis of more than 70 amine products bearing various functional groups in high chemoselectivity. Moreover, this mild system achieved >2000 TONs (turnover numbers) for the transfer hydrogenation of nitriles. [ABSTRACT FROM AUTHOR]

The first organocatalytic synthesis of terminal propargylic amines from aldehydes via tandem amination/Seyferth-�Gilbert alkynylation has been developed. The described protocol provides the formal addition products of acetylene (HC≡CH) to ali�phatic imines, which are not easily obtained directly. [ABSTRACT FROM AUTHOR]

Abstract: A short review on the development and application of chiral primary amine catalysts in organocatalytic enantioselective reactions has been described. [Copyright &y& Elsevier]