No abstract

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Magnesium alkoxides undergo a hydride‐transfer oxidation with benzaldehyde as the oxidant. This magnesium variant of the Oppenauer oxidation was used for the synthesis of polyfunctional biaryl ketones. LiCl was found to promote this reaction by enhancing the solubility of magnesium alkoxides. This mild oxidation method was especially useful for preparing ketones bearing a metallocenyl unit as well as various new ferrocenyl ketones and tricarbonylchromium complexes. This last class of ketones was reduced with the CBS catalyst (CBS=Corey–Bakshi–Shibata, diphenyl oxazaborolidine) to chiral benzhydrol complexes with high enantioselectivity enabling an asymmetric synthesis of electron‐rich or ‐poor benzhydryl alcohols (up to 94 % ee).

No abstract

[reaction: see text] (-)-N,N-Dimethylaminoisoborneol ((-)-DAIB) was found to be an excellent ligand for the enantioselective addition of Reformatsky reagents to aromatic and aliphatic aldehydes. Enantioselectivities up to 93% ee were obtained with sulfur-containing aldehydes.