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The reaction of alkyl- and aryl- aldimines bearing various electron-withdrawing groups on the nitrogen atom with the lithium derivative of (S)-tert-butylsulfinylferrocene is reported. New aminosulfoxides were obtained with complete diastereocontrol when Dpp or Boc groups were used and the determination of absolute configuration ([S.sub.s],[S.sub.Fe],S) was done by single-crystal X-ray analysis and chemical correlation.

The protonation of 2-pyridylalkylamines (PAA) was investigated through quantum chemical calculations at a DFT level of theory in dichloromethane solution. Two different PAA–H+ species and a dynamic equilibrium between protonated forms were evidenced. The overall geometry of the PAA–H+ promoters is strongly influenced by the nature of the moiety and the absolute configuration of the pseudobenzylic stereocenter. Thus, PAA–H+ complexes were used as organocatalysts in the enantioselective hydroxyalkylation of indole derivatives. The combination of PAA, a strong acid and a soft counter-ion was found to be a mandatory parameter to achieve high yields and selectivities allowing hydroxyalkylation of both N–H and N-protected indoles using a unique catalytic system. [ABSTRACT FROM AUTHOR]

A new method to prepare enantioenriched sulfinates was developed to obtain optically active ortho-methylsulfinyl(phenylphosphonates). It consists of a diastereoselective oxidation of sulfenates to sulfinates. Additionally, preliminary results concerning the synthesis of ortho-phophonylated benzylic thiol derivatives via a new P-S to P-C [1,4]-rearrangement and a first synthetic application of these compounds are also described. [ABSTRACT FROM AUTHOR]

New Yb(OTf)(3)-pyridylalkylamine complexes have been employed as chiral Lewis acids in the enantioselective Friedel-Crafts alkylation of indole derivatives with trifluoropyruvates. The influence of the substituents as well as the configuration of the ligands have been studied and allowed us to reach enantiomeric excesses up to 83%.