The Mechanism of Alkene Elimination from Protonated Toluenesulphonamides Generated by Electrospray Ionisation
作者:Amie Saidykhan、Jenessa Ebert、William H.C. Martin、Richard T. Gallagher、Richard D. Bowen
DOI:10.1255/ejms.1427
日期:2016.8
The positive ion electrospray massspectra of a range of sulphonamides of general structure CH3C6H4SO2NHR1 [R1 = C n H2n+1 (n = 1–7), C n H2n-1 (n = 3, 4), C6H5, C6H5CH2 and C6H5CH(CH3)] and CH3C6H4SO2NR1R2 [R1, R2 = C n H2n+1 (n = 1–8)] are reported and discussed. The protonated sulphonamides derived from saturated primary and secondary aliphatic amines generally fragment to only a limited extent
一系列一般结构为 CH3C6H4SO2NHR1 [R1 = C n H2n+1 (n = 1–7), C n H2n-1 (n = 3, 4), C6H5, C6H5CH2 和 C6H5CH( CH3)] 和 CH3C6H4SO2NR1R2 [R1, R2 = C n H2n+1 (n = 1–8)] 进行了报道和讨论。除非通过碰撞激发能量,否则衍生自饱和脂肪族伯胺和仲胺的质子化磺酰胺通常仅在有限程度上碎裂。观察到两种一般的断裂:首先,消除烯烃,C n H2n,通过从氮上的 C n H2n+1 烷基之一夺氢获得;其次,裂解形成 CH3C6H4SO2+。通过研究 [M + H – C n H2n]+ 信号强度随氮上烷基取代基结构的变化,以及监测与从质子化的不对称磺酰胺中丢失不同的烯烃,其中两个不同的烷基与氮相连。这种断裂有利于烷基在直接连接到氮的碳原子上的支化,因此表明它涉及一种机制,其中通
Stereoinversion of Unactivated Alcohols by Tethered Sulfonamides
作者:Paul T. Marcyk、Latisha R. Jefferies、Deyaa I. AbuSalim、Maren Pink、Mu‐Hyun Baik、Silas P. Cook
DOI:10.1002/anie.201812894
日期:2019.2.4
remains an undeveloped area of organic synthesis. Moreover, catalytic activation of this difficult electrophile with predictable stereo-outcomes presents an even more formidable challenge. Described herein is a simple iron-based catalyst system which provides the mild, direct conversion of secondary and tertiary alcohols to sulfonamides. Starting fromenantioenriched alcohols, the intramolecular variant
A Hydrazone-Based <i>exo</i>
-Directing-Group Strategy for β C−H Oxidation of Aliphatic Amines
作者:Zhongxing Huang、Chengpeng Wang、Guangbin Dong
DOI:10.1002/anie.201600912
日期:2016.4.18
group (DG) strategy developed for the functionalization of unactivated primary β C−H bonds of aliphaticamines. Conveniently synthesized from protected primary amines, the hydrazone DGs are shown to site‐selectively promote the β‐acetoxylation and tosyloxylation via five‐membered exo‐palladacycles. Amines with a wide scope of skeletons and functional groups are tolerated. Moreover, the hydrazone DG
A new and convenient method for the construction of sulfonamides via a copper-catalyzed oxidative coupling between sodium sulfinates and amines with 1 atm O2 or DMSO as the oxidant was described. This method provides efficient and robust synthesis of functional sulfonamides in good yields and excellent chemoselectivity. And detailed mechanistic studies showed that this transformation may go through a single electron transfer (SET) pathway.