Copper-catalyzed asymmetric sulfoxidation of aryl benzyl and aryl alkyl sulfides, using aqueous hydrogen peroxide as the oxidant, has been investigated. A relationship between the steric effects of the sulfide substituents and the enantioselectivity of the oxidation has been observed, with up to 93% ee for 2-naphthylmethyl phenyl sulfoxide, in modest yield in this instance (up to 30%). The influence
Investigation of steric and electronic effects in the copper-catalysed asymmetric oxidation of sulfides
作者:Graham E. O'Mahony、Kevin S. Eccles、Robin E. Morrison、Alan Ford、Simon E. Lawrence、Anita R. Maguire
DOI:10.1016/j.tet.2013.08.063
日期:2013.11
in the copper-catalysed asymmetricoxidation of aryl benzyl, aryl alkyl and alkyl benzyl sulfides have been investigated. The presence of an aryl group directly attached to the sulfur is essential to afford sulfoxides with high enantioselectivities, with up to 97% ee for 2-naphthyl benzyl sulfoxide, the highest enantioselectivity achieved to date for copper-catalysed asymmetric sulfoxidation. In contrast
Herein we reported an efficient palladium-catalyzed enantioselective arylation of both alkyl and aryl sulfenate anions to deliver various chiral sulfoxides in good yields (up to 98%) with excellent enantioselectivities (up to 99% ee) by the use of our developed chiral O,P-ligands (PC-Phos). PC-Phos are easily prepared in shortsteps from inexpensive commercially available starting materials. The single-crystal
The first genuinely promising porphyrin-inspired manganese-catalyzed asymmetricsulfoxidation method using hydrogen peroxide has been successfully developed, allowing for rapidly oxidizing (0.5–1.0 h) a wide variety of sulfides in high yields with excellent enantioselectivities (up to >99% ee).
Asymmetricsulfoxidation catalyzed by a biomimeticmanganese complex under continuous‐flow microreactor is described. The reaction is conducted in microreactor, it can rapidly (<4 min) oxidize a wide scope of sulfides with high yield (up to 91%) and excellent enantioselectivity (up to 99% ee), and allows shorter reaction times, easier scale‐up and lower catalyst loadings than its batchwise counterpart