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A practical stereoselective iodide-lithium exchange was used in the first general preparation of functionalized stereodefined acyclic secondary nonstabilized lithium reagents from the corresponding secondary alkyl iodides. These lithium reagents react with various electrophiles including carbon electrophiles with high retention of configuration. Kinetic data on the configurational stability of these acyclic alkyllithium reagents are given. This methodology offers a new entry to chiral synthons for the stereoselective synthesis of open-chain molecules.

3,4,5-Triamino-substituted pyridines are avid for electrophiles but are still willing to give them back. In these compounds three amino groups conjoin their forces into the heterocyclic nitrogen, making it a powerful Lewis base. A short and efficient synthesis is described, and the origin of its unique activity in nucleophilic organocatalysis is rationalized by kinetics and thermodynamic quantifications.

1 - Article; The Michael addition to nitroolefins of manganese enolates derived from an array of ketones is reported. The desired 1,4-adducts are obtained in high yield and excellent diastereo- and regioselectivity, the sole kinetic adduct being obtained in the case of nonsymmetrical ketones. The effect of a thiourea-type organocatalyst on the addition of several representative nitroolefins to the kinetic manganese enolate derived from isopropyl ethyl ketone is also reported.