Carbon nitrogen double bond, hydrosilylation

The carbon-nitrogen double bonds of nitrones N1-N3 (Fig. 14) were catalytical-ly reduced with diphenylsilane in the presence of Ru2Cl4(Tol-BINAP, L24)2(NEt3) to give hydroxylamines in high % ees [56]. The hydroxylamine HI was obtained in 63% yield with 86% ee (S) and the hydroxylamine H3 was formed in 91% ee. It was also proposed that this process opened a new access to optically active amines from racemic amines, via nitrones and hydroxylamines. The iron complex [(Cp)2Fe2(HPMen2> L25)(CO)2] was reported to be a catalyst in the asymmetric hydrosilylation of ketones under irradiation, where acetophenone was reduced in up to 33% ee [57]. 

Kagan reported on asymmetric hydrosilylation of prochiral compounds with carbon-nitrogen double bonds.TV-(a-methylbenzylidene)benzyl-... 

In 1999 [22] and 2001 [23], Matsumura and co-workers reported the first examples of stereoselective hydrosilylation with HSiCla and (5)-proline derivatives as effective activators. These works can be considered as milestones for the asymmetric reduction of ketones and imines using HSiCla as reducing agent and paved the road to the synthesis of other related systems. Since then, considerable efforts have been devoted to the development of efficient catalysts for the reduction of carbon-nitrogen double bonds, and remarkable progress has been made. 

ASYMMETRIC REDUCTION OF CARBON-NITROGEN DOUBLE BOND pia HYDROSILYLATION... 

Asymmetric Reduction of Carbon-Nitrogen Double Bond via Hydrosilylation. 215... 

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