Radical Enamination of Vinyl Azides: Direct Synthesis of N-Unprotected Enamines
摘要:
An electron-withdrawing-group-generable radical-induced enamination of vinyl azides is reported, which results in a variety of beta-functionalized N-unprotected enamines in a stereoselective manner. A plausible mechanism involving an unusual 1,3-H transfer of in situ generated iminyl radical intermediate was proposed on the basis of experimental results and DFT calculations.
The Iridium-catalyzed enantioselective couplingreaction of vinyl azides and allylic electrophiles is presented and provides access to β-chiral carbonyl derivatives. Vinyl azide are used as acetamide enolate or acetonitrile carbanion surrogates, leading to γ,δ-unsaturated β-substituted amides as well as nitriles with excellent enantiomeric excess. The products are readily transformed into chiral N-containing
Copper-catalyzed [2+3]-annulation of N–H imines with vinyl azides: access to polyaryl 2<i>H</i>-imidazoles
作者:Zhongzhi Zhu、Hanze Lin、Baihui Liang、Junjie Huang、Wanyi Liang、Lu Chen、Yubing Huang、Xiuwen Chen、Yibiao Li
DOI:10.1039/c9cc10042c
日期:——
A practical method for the synthesis of 2H-imidazoles via a [2+3] annulation of N-H imines with vinylazides using a copper catalyst is developed. In this conversion, environmentally friendly oxygen is used as the sole oxidant and N2 and H2O are the only by-products. The catalytic transformation, operating under mild conditions, is operationally simple and is considered as a readily available catalytic
A protocol to link alcohols with vinyl azides has been established through fluoro- or bromo-alkoxylation of vinyl azides to provide α-alkoxy-β-haloalkyl azides. A series of primary and secondary alcohols including natural products and their derivatives such as sugars and steroids were successfully anchored with vinyl azides. The as-prepared cyanine dye linked testosterones were capable of rapid cell
Electrochemically enabled synthesis of sulfide imidazopyridines <i>via</i> a radical cyclization cascade
作者:Ping-Fu Zhong、Hong-Min Lin、Lin-Wei Wang、Zu-Yu Mo、Xiu-Jin Meng、Hai-Tao Tang、Ying-Ming Pan
DOI:10.1039/d0gc02125c
日期:——
Owing to the inert nature of the pyridine ring and high activity of iminyl radicals, the reaction between pyridine and iminyl radicals remains a significant challenge. In this paper, we report the synthesis of sulfide imidazo[1,2-a]pyridines from vinyl azides, thiophenols, and pyridines via a radical [3 + 2] cycloaddition. Promoting inert pyridine and highly active iminyl radicals to participate in
由于吡啶环的惰性和亚氨基自由基的高活性,吡啶和亚氨基自由基之间的反应仍然是一个重大挑战。在本文中,我们报告了通过自由基[3 + 2]环加成反应从乙烯基叠氮化物,硫酚和吡啶合成硫化物咪唑并[1,2- a ]吡啶。促进惰性吡啶和高活性亚氨基自由基参与该分子间环加成过程是该方案的显着特征。所制备的硫化物咪唑并吡啶支架的优异抗肿瘤活性证明了开发的合成方案的合成实用性。
Rh(<scp>ii</scp>)-catalyzed cycloadditions of 1-tosyl 1,2,3-triazoles with 2H-azirines: switchable reactivity of Rh-azavinylcarbene as [2C]- or aza-[3C]-synthon
作者:Yuanhao Wang、Xiaoqiang Lei、Yefeng Tang
DOI:10.1039/c5cc00268k
日期:——
The Rh(II)-catalyzed formal [3+2] and [3+3] cycloadditions of 1-tosyl 1,2,3-triazoles with 2H-azirines have been developed, which enable the efficient synthesis of polysubstituted 3-aminopyrroles and 1,2-dihydropyrazines, respectively. The reported [3+2] cycloaddition represents the first application of 1-sulfonyl 1,2,3-triazole as a [2C]-component in relevant cycloaddition reactions.