Valine-derived formamide

Asymmetric variants of imine reduction have also been developed towards enantiopure aziridines. Reduction of chiral /V-tert-butanesulfinyl a-halo imines afforded enantiopure aziridines in good to excellent yields <07JOC3211>. Enantioselective catalytic reduction of a-chloroimines utilizing metal-free L-valine-derived formamide 45 followed by base-mediated ring closure provided aziridines with preserved enantiopurity <07AG(I)3722>. 

In another context, an L-valine-derived formamide was applied by Kocov-sky s group as an organocatalyst to the asymmetric hydrosilylation of enam-ines, allowing a direct access to a range of jS-amino add derivatives. This method relied on the fast equilibration between the enamine and the imine... 

Scheme 2.114 DKR hydrosilylation of enamines catalysed by L-valine-derived formamide.

Table4.11 Reduction of ketimines 6 with trichlorosilane, catalyzed by the valine derived N methyl formamides (S) 23, (S) 48 52 ...

---