Practical and Highly Selective Sulfur Ylide Mediated Asymmetric Epoxidations and Aziridinations Using an Inexpensive, Readily Available Chiral Sulfide. Applications to the Synthesis of Quinine and Quinidine
作者:Ona Illa、Muhammad Arshad、Abel Ros、Eoghan M. McGarrigle、Varinder K. Aggarwal
DOI:10.1021/ja9100276
日期:2010.2.17
one-step synthesis of a chiral sulfide which exhibits outstanding selectivities in sulfur ylide mediated asymmetric epoxidations and aziridinations. In particular reactions of benzyl and allylic sulfonium salts with both aromatic and aliphatic aldehydes gave epoxides with perfect enantioselectivities and the highest diastereoselectivities reported to date. In addition reactions with imines gave aziridines
Practical and Highly Selective Sulfur Ylide-Mediated Asymmetric Epoxidations and Aziridinations Using a Cheap and Readily Available Chiral Sulfide: Extensive Studies To Map Out Scope, Limitations, and Rationalization of Diastereo- and Enantioselectivities
作者:Ona Illa、Mariam Namutebi、Chandreyee Saha、Mehrnoosh Ostovar、C. Chun Chen、Mairi F. Haddow、Sophie Nocquet-Thibault、Matteo Lusi、Eoghan M. McGarrigle、Varinder K. Aggarwal
DOI:10.1021/ja405073w
日期:2013.8.14
The chiral sulfide, isothiocineole, has been synthesized in one step from elemental sulfur, γ-terpinene, and limonene in 61% yield. A mechanism involving radical intermediates for this reaction is proposed based on experimental evidence. The application of isothiocineole to the asymmetric epoxidation of aldehydes and the aziridination of imines is described. Excellent enantioselectivities and diastereoselectivities
A C 2 -symmetric sulfide 6 has been synthesized from cheap L-tartaric acid. It was found that sulfide 6 could perform a tandem reaction with benzyl bromide and tosyl imines to give (2S,3S)-aziridines 9a-9g with good to excellent enantioseletivities (up to 96% ee).
AC 2 -对称硫化物6已由廉价的L-酒石酸合成。发现硫化物 6 可以与苄基溴和甲苯磺酰亚胺进行串联反应,得到 (2S,3S)-氮丙啶 9a-9g,具有良好至极好的对映选择性(高达 96% ee)。
The First Example of Catalytic Aziridination Mediated by Arsonium Ylides: Preparation of<i>trans-</i>Pentafluorophenyl-Containing Aziridines
作者:Shizheng Zhu、Shifa Zhu、Yuanxi Liao
DOI:10.1055/s-2005-868498
日期:——
formation of aziridines from tosyl imines and aromatic diazo compounds in a one-pot reaction. It is the first example of catalytic aziridination mediated by arsonium ylides. It gave aziridines in excellent diastereoselectivity with pentafluorophenyl diazomethane as the substrate. This catalytic reaction is complementary with the reaction mediated by sulfurylides.