080303-氧化反应.ppt

It must be mentioned that IBX is particularly useful in selective oxidations of primary alcohols, leading to hydroxyaldehydes present as lactols. (a) Corey, E. J.; Palani, A.; Tetrahedron Lett. 1995, 36, 3485. (b) Amano, S.; Fujiwara, K.; Murai, A.; Chem. Lett. 1998, 5, 409. The very common TEMPO-mediated Anelli’s protocol for the oxidation of alcohols, involving a biphasic CH2Cl2-water mixture containing catalytic TEMPO, or an analogue thereof, and sodium hypochlorite as a secondary oxidant, shows a great selectivity for the oxidation of primary alcohols in the presence of secondary ones and has found some use in synthetic organic chemistry. Nicolaou,K. C.; Ray, M.; Finaly, V.; Ninkovic, S.; Sarabia, F.; Tetrahedron 1998, 54, 7127. RuCl2(PPh3)3 Stoichiometric RuCl2(PPh3)3 in benzene shows a remarkable selectivity for the oxidation of primary alcohols in the presence of secondary ones. * Oxidation reactions (2) Hypervalent Iodine-based oxidation Ruthenium-based oxidation Tempo-mediated oxidation Selective oxidation of 1o Alcohol vs 2o Alcohol Selective oxidation of 2o Alcohol vs 1o Alcohol ? 应用Cr系列氧化剂，活化的二甲亚砜氧化剂，双键往往发生重排。 在化学转化中，保持化合物的立体构型是至关重要的。对于易消旋化的化合物尤其要选择温和的条件。 其它Hypervalent Iodine 氧化剂 The water soluble IBX analogue 46 has been prepared. It is capable of oxidizing allylic and benzylic alcohols in water solution with no over-oxidation being observed to acids, in spite of the presence of a great excess of water. The compound 46 is not able of oxidizing aliphatic alcohols. 其它Hypervalent Iodine 氧化剂 其它Hypervalent Iodine 氧化剂 Compound 48 possesses the distinctive advantages of being air-stable, non-explosive and soluble in common organic solvents. Chiral oxidants 49 are able to oxidize alcohols, and possessing a limited ability for the enantioselective oxidation of non-symmetric sulfides. Ruthenium-based Oxidation RuO4，Ruthenium Tetroxide RuO4-, Perruthenate RuO42- , Ruthenate Ruthenium oxidants are very efficient, but their prices are prohibitive. A great research