Chiral SO/P hybrid ligands: an enantioselective switch in palladium-catalyzed asymmetric allylic etherifications
摘要:
A variety of chiral tert-butanesulfinylphosphine ligands were prepared and applied to the palladium-catalyzed asymmetric allylic etherification of 1,3-diphenylpropenyl acetate with alcohols. Excellent yields and moderate enantioselectivities were obtained. The absolute configuration of the etherification products was evidently switched only through the position change of the substituent on the P-aryl groups. (C) 2012 Elsevier Ltd. All rights reserved.
An efficient rhodiumcomplex catalyst system was developed by using a class of simple tert‐butanesulfinylphosphines as bidentate ligands, which solely bear sulfur chirality and combine the advantages of both sulfoxide and phosphineligands. Excellent activities (in 0.5 hour, up to 99% yield) and enantioselectivities (up to 98% ee) were displayed in Rh‐catalyzed asymmetric 1,4‐additions under mild conditions
A General and Expeditious One-Pot Synthesis of Sulfoxides in High Optical Purity from Norephedrine-Derived Sulfamidites
作者:José L. García Ruano、Carlos Alemparte、M. Teresa Aranda、María M. Zarzuelo
DOI:10.1021/ol027232i
日期:2003.1.1
A general and simple procedure for preparing any kind of enantiomerically enriched sulfoxide starting from norephedrine-derived N-benzyloxycarbonylsulfamidite 3a is reported. After one-pot reaction of 3a with RMgX, HBF(4), and R'MgX, a variety of sulfoxides 6 are obtained in ee usually higher than 93% and isolated yields ranging between 50 and 78%. The obtained configuration is tunable by simply electing
Chiral Brønsted-Acid-Catalyzed Asymmetric Oxidation of Sulfenamide by Using H<sub>2</sub>O<sub>2</sub>: A Versatile Access to Sulfinamide and Sulfoxide with High Enantioselectivity
Herein, we describe an example of catalyticasymmetricsynthesis of sulfinamides. Aromatic sulfenamides were chosen as useful substrates, because of the indispensable N–H bond, which could form an efficient hydrogen bond with chiral phosphoric acid. H2O2 (35%) was used as the terminal oxidant for preparation of sulfinamides in high yields and enantioselectivities, which could be easily derivatized
在本文中,我们描述了亚磺酰胺催化不对称合成的一个例子。选择芳香亚磺酰胺作为有用的底物,因为它不可缺少的NH键可以与手性磷酸形成有效的氢键。H 2 O 2(35%)被用作末端氧化剂,以高收率和对映选择性制备亚磺酰胺,可以很容易地衍生为亚砜和其他亚磺酰胺,而不会损失对映选择性。