Reversal of Diastereofacial Selectivity in Hydride Reductions of <i>N</i>-<i>tert</i>-Butanesulfinyl Imines
作者:John T. Colyer、Neil G. Andersen、Jason S. Tedrow、Troy S. Soukup、Margaret M. Faul
DOI:10.1021/jo0609834
日期:2006.9.1
same sulfinyl imine starting materials and changing the reductant to L-Selectride, the stereoselectivity could be efficiently reversed to afford the opposite product diastereomer in high yield and selectivity.
Hydroxymethylation of cyclic tert-butanesulfinylketimine-derived lithium enamides with methoxymethanol proceeds with excellent diastereoselectivity (99:1 dr). Methoxymethanol is a stable and easy-to-handle source of anhydrous monomeric formaldehyde in the reaction with lithium enamides. Cyclic α-hydroxymethyl ketimines undergo highly diastereoselective reduction to syn- or anti-1,3-amino alcohols.
Diastereoselective Hydroxylation of <i>N</i>-<i>tert</i>-Butanesulfinyl Imines with 2-(Phenylsulfonyl)-3-phenyloxaziridine (Davis Oxaziridine)
作者:Anupam Karmakar、Po-Cheng Yu、Femil J. Shajan、Vijay K. Chatare、William A. Sabbers、Eduardo M. Sproviero、Rodrigo B. Andrade
DOI:10.1021/acs.orglett.2c02513
日期:2022.9.16
The diastereoselective α-hydroxylation of N-tert-butanesulfinyl metallodienenamine and metalloenamines with Davis oxaziridine affords α-hydroxy N-sulfinyl imines with 50–88% yield and up to 98:2 diastereomeric ratio. Dramatic changes in diastereoselectivity and stereoselectivity were observed by choice of metal bases. The mechanistic understanding for the switch in diastereoselectivity was assisted
N-叔丁烷亚磺酰基金属二烯胺和金属烯胺与 Davis oxaziridine的非对映选择性 α-羟基化得到 α-羟基N-亚磺酰基亚胺,产率为 50-88%,非对映体比例高达 98:2。通过选择金属碱可以观察到非对映选择性和立体选择性的显着变化。DFT 计算模型有助于对非对映选择性转换的机理理解,这表明面部方法受氮杂烯醇化物几何形状的控制。描述了 1,2-氨基醇不对称合成的一锅法。
Cycloaddition of Chiral <i>tert</i>-Butanesulfinimines with Trimethylenemethane
作者:George Procopiou、William Lewis、Gareth Harbottle、Robert A. Stockman
DOI:10.1021/ol400720b
日期:2013.4.19
The cycloaddition of chiral tert-butanesulfinimines with trimethylenemethane is found to give facile access to methylene-pyrrolidines with good yields and diastereoselectivities. The full scope of the cycloaddition is explored, and a range of transformations of the formed methylenepyrrolidines to give a range of functionalized chiral pyrrolidines is presented.
Asymmetric Synthesis of 1,2-Diamines bearing Tetrasubstituted Centers from Nonstabilized Azomethine Ylides and <i>N</i>-Sulfinylketimines under Brønsted Acid Catalysis
作者:Cristina Izquierdo、Francisco Esteban、José Luis García Ruano、Alberto Fraile、José Alemán
DOI:10.1021/acs.orglett.5b03251
日期:2016.1.4
The first asymmetric cycloaddition of nonstabilized azomethine ylide and N-sulfinylimines is presented. In reactions with aryl-alkyl and heteroaryl-alkyl ketimines, excellent diastereoselectivities and good yields are obtained in all cases, regardless of the electronic character of the substituents at the aromatic rings. Moreover, the cycloadducts obtained can easily be deprotected in acid media, giving access to free 1,2-diamines which are prevalent in many natural and pharmaceutical products.