Kloetzing Ralf J, Krasovskiy Arkady, Knochel Paul
Universität Zürich, Organisch-chemisches Institut, Winterthurerstrasse 190, 8057 Zürich, Switzerland.
Chemistry. 2007;13(1):215-27. doi: 10.1002/chem.200600738.
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).
醇镁与苯甲醛作为氧化剂发生氢转移氧化反应。这种奥本瑙尔氧化反应的镁变体用于合成多官能团联芳基酮。发现氯化锂通过提高醇镁的溶解度来促进该反应。这种温和的氧化方法对于制备带有茂金属单元的酮以及各种新型二茂铁基酮和三羰基铬配合物特别有用。最后一类酮用CBS催化剂（CBS = 科里-巴克希-柴田，二苯基恶唑硼烷）还原为具有高对映选择性的手性二苯甲醇配合物，从而实现富电子或贫电子二苯甲醇的不对称合成（对映体过量高达94%）。
