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An organocatalytic asymmetric domino Michael/α‐alkylation reaction between enals and non‐stabilized alkyl halides has been developed. Chiral secondary amine catalyzed cyclization reaction of 1‐bromo‐3‐nitropropane with α,β‐unsaturated aldehydes provides 1,2,3‐trisubstituted cyclopentane carbaldehydes with high diastereo‐ (dr up to 8 : 1) and enantioselectivities (ee up to 96 %). [ABSTRACT FROM AUTHOR]

Abstract: The highly enantioselective organocatalytic α-selenylation reaction of aldehydes using a hypervalent iodine compound as an oxidative agent from commercially available phenyl diselenide under mild oxidative conditions is described. This transformation affords α-selenyl aldehydes in good yields and with excellent enantioselectivities. By using hypervalent iodine compounds, it opens up a suitable and alternative way for the preparation of biologically active building blocks such as β-hydroxy alcohols, α-amino acids, and α-hydroxy esters. [Copyright &y& Elsevier]

The successful α-selenylation methodology is also applicable to β-keto esters like (V). [ABSTRACT FROM AUTHOR]

Abstract: A highly enantioselective organocatalytic fluoromalonate addition to α,β-unsaturated aldehydes is reported. The reaction is catalyzed by simple and commercially available secondary amines, affording the corresponding 1,4-adducts with high yields and enantioselectivities. [Copyright &y& Elsevier]