Directed C–C bond cleavage of a cyclopropane intermediate generated from<i>N</i>-tosylhydrazones and stable enaminones: expedient synthesis of functionalized 1,4-ketoaldehydes
-quaternary centers via regioseletive C-C bond activation has been described. Through cyclopropanation of bench-stable enaminones with in situ generated diazo reagents from N-tosylhydrazones, followed by selective C-C bond cleavage of the cyclopropane ring affords the 1, 4-ketoaldehyde derivatives in good to excellent yields. This method works with broad substrate scope and high regioseletivity.
Palladium(0)-catalyzed C(sp<sup>3</sup>)–Si bond formation <i>via</i> formal carbene insertion into a Si–H bond
作者:Zhenxing Liu、Jingfeng Huo、Tianren Fu、Haocheng Tan、Fei Ye、Mohammad Lokman Hossain、Jianbo Wang
DOI:10.1039/c8cc06768f
日期:——
Pd(0)-Catalyzed formal carbene insertion into Si–H bonds has been achieved as an efficient method for C(sp3)–Si bond formation. The reaction, which uses readily available N-tosylhydrazones as the diazo precursors, is highly efficient and shows a wide substrate scope. Rh(II) and Cu(I) salts, which are the widely used catalysts for carbene insertion reactions, have been proved to be ineffective for the
Pd(0)-Catalyzed Carbene Insertion into Si–Si and Sn–Sn Bonds
作者:Zhenxing Liu、Haocheng Tan、Tianren Fu、Ying Xia、Di Qiu、Yan Zhang、Jianbo Wang
DOI:10.1021/jacs.5b09135
日期:2015.10.14
The first Pd(0)-catalyzed carbene insertion into Si-Si and Sn-Sn bonds has been realized by using N-tosylhydrazones as the carbene precursors. Geminal bis(silane) and geminal bis(stannane) derivatives were obtained in good to excellent yields under mild conditions. Migratory insertion of Pd carbene is supposed to be the key step for the reaction.
Recyclable Copper(I)-Catalyzed Cross-Coupling of Trialkylsilylethynes and <i>N</i>-Tosylhydrazones Leading to the Formation of C(sp)–C(sp<sup>3</sup>) Bonds
作者:Qian Ye、Wencheng Huang、Li Wei、Mingzhong Cai
DOI:10.1021/acs.joc.2c02691
日期:2023.3.3
A highly efficient heterogeneous copper(I)-catalyzed cross-coupling of trialkylsilylethynes with N-tosylhydrazones has been achieved in dioxane at 90–110 °C via the Cu carbenemigratoryinsertion with an SBA-15-immobilized l-proline-Cu(I) complex [SBA-15-l-Proline-CuI] as the catalyst and LiOtBu as the base, leading to the formation of C(sp)–C(sp3) bonds. The reaction generates a wide variety of a
通过 Cu 卡宾迁移插入和 SBA-15-固定的l-脯氨酸-Cu (I ) 络合物 [SBA-15- l -Proline-CuI] 作为催化剂和 LiO t Bu 作为碱,导致 C(sp)–C(sp 3 ) 键的形成。该反应以中高产率生成多种烷基三烷基甲硅烷基炔烃。这种新型多相铜 (I) 配合物具有与均相 CuI 相当的催化效率,并且可以通过简单的离心过程轻松回收,并且可回收多达 12 次而不会显着损失活性。
Denitrogenation of tosylhydrazones: synthesis of aryl alkyl sulfones catalyzed by a phenalenyl-based molecule
作者:Shiv Kumar、Paramita Datta、Anup Bhunia、Swadhin K. Mandal
DOI:10.1039/d3cy01194a
日期:——
Sulfur-containing organic molecules such as sulfones are prevalent in pharmaceuticals and agrochemicals. Herein, we report the first transition-metal-free process for in situ denitrogenation of tosylhydrazones to produce a diverse array of aryl alkyl sulfones. We have used phenalenyl-based odd alternant hydrocarbon as a photoredox catalyst for denitrogenation of tosylhydrazones, where the phenalenyl