Highly diastereoselective synthesis of aza-diels-alder reaction of danishefsky diene wiht glyoxylate imines

Aza-Diels-Alder reaction is an exceptionally powerful synthetic method for the construction of six-membered nitrogen-heterocycles.[1-3] The reaction of Danishefsky's diene 1 with iminoacetates 2 (imines of glyoxylates) provides a convenient protocol for the synthesis of pipiridone adducts 3 (Scheme 1). In this context, we have performed the synthesis of various cycloadducts, precursors of a wide variety of chiral piperidines with potential use as non-natural amino acids or as precursors of biologically active compounds, including iminosugars (glycomimetics)

Estudos de Cianação Enantiosselectiva de Aldeídos e Contribuição para a Síntese de Aza-Açúcares Piperidínicos

Tese de doutoramento em Química, no ramo de especialização em Síntese Orgânica, apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbr

Enantioselective trimethylsilylcyanation of benzaldehyde using pyrrolidine-based chiral salen ligands

The in situ formed Ti(IV) complexes of several pyrrolidine-based chiral salen ligands derived from natural (L)-tartaric acid were evaluated as catalysts in the enantioselective trimethylsilylcyanation of benzaldehyde. The catalysts were found to be very active, producing the corresponding product, O-trimethylsilylmandelonitrile, in high yields (>94%) and enantioselectivities of up to 88%