In this review, recent advances in catalytic asymmetric hydrophosphonylation of aldehydes and imines are discussed. We also summarize several proposed mechanisms for the different possibilities of asymmetric induction and the application of this catalytic methodology to the enantioselective synthesis of α‐amino and α‐hydroxy phosphonates. A variety of metal‐based chiral catalysts as well as several organic catalysts have been exploited as suitable systems for the preparation of enantiomerically pure phosphonates. The recent evolution and future trends of those and other catalytic systems are described.

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Asymmetric aza‐Henry reactions provide excellent routes for the synthesis of optically active organic compounds bearing two vicinal different nitrogenated functionalities that can be further transformed into a variety of interesting compounds such as 1,2‐diamines or α‐amino acids. The catalytic asymmetric version of the reaction (also called the nitro‐Mannich reaction) provides highly efficient access to enantiomerically pure compounds. Both metal‐based and organic catalysts can be used to promote these reactions in a enantioselective way; in particular, a great variety of different organocatalysts – including thioureas, N‐oxides, quaternary ammonium salts and chiral Brønsted acids – have demonstrated their efficiency, as has recently been reported by several research groups. In addition, considerable effort is being made in controlling the syn/anti diastereoselectivities of these reactions when substituted nitroalkanes are used as substrates. In this microreview recent advances, including scope and limitations, are discussed and applications of different catalytic systems for catalytic asymmetric aza‐Henry reactions are presented.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

The enantioselective alkylation of α,β-unsaturated aldehydes with stabilized carbocations as electrophiles via the activation as dienamine intermediates is described. This unique application of dienamine catalysis allows for the first enantioselective γ-alkylation of linear α,β-unsubstituted enals.