A novel protocol for the synthesis of α-aryl nitriles has been successfully achieved via a copper-catalyzed cyanation of N-tosylhydrazones employing thiocyanate as the source of cyanide. The features of this method include a convenient operation, readily available substrates, low-toxicity thiocyanate salts, and a broad substrate scope.
Pd-Catalyzed Highly Regio- and Stereoselective Formation of C–C Double Bonds: An Efficient Method for the Synthesis of Benzofuran-, Dihydrobenzofuran-, and Indoline-Containing Alkenes
A highly regio- and stereoselective C–C double bond formation reactionvia Pd-catalyzed Heck-type cascade process with N-tosylhydrazones has been developed. Various N-tosylhydrazones derived from both ketones and aldehydes are found to be efficient substrates to provide di- and trisubstitutedolefins with high regio- and stereoselectivity. Furthermore, this reaction has a good functional group tolerance
Transition‐Metal‐Free Cascade Enyne Rearrangement and Cyclopropanation of Allenylphosphine Oxides with
<i>N</i>
‐Tosylhydrazones Accessing Alkynylcyclopropane Derivatives
We disclose an concise synthesis of alkynylcyclopropane derivatives containing adjacent quaternary carbon centers via a transition-metal free cascade enyne rearrangement and cyclopropanation process. This methodology, started from a variety of allenylphosphine oxides and N-tosylhydrazones, features the advantage of transition-metal-free, operational simplicity, wide substrate scope and good functional
Regioselective One-Step Synthesis of Pyrazoles from Alkynes and N-Tosylhydrazones: [3+2] Dipolar Cycloaddition/[1,5] Sigmatropic Rearrangement Cascade
作者:M. Carmen Pérez-Aguilar、Carlos Valdés
DOI:10.1002/anie.201301284
日期:2013.7.8
Rearrangement under control: A wide variety of 3,4,5‐ and 1,3,5‐trisubstituted pyrazoles can be prepared from tosylhydrazones of ketones and terminal alkynes through the title reaction sequence (see scheme; Ts=4‐toluenesulfonyl). The rearrangement, and therefore, the regioselectivity of the reaction is controlled by the nature of the substituents of the tosylhydrazone.
Access to Fluorescent Azines from N-Heterocyclic Carbene Precursors and <i>N</i>
-Tosylhydrazones
作者:Siping Wei、Shuangxun Li、Changyou Chen、Zhonghong He、Xi Du、Li Wang、Chun Zhang、Qin Wang、Lin Pu
DOI:10.1002/adsc.201700241
日期:2017.6.6
An efficient synthesis of azines from the reaction of N‐heterocycliccarbene precursors with N‐tosylhydrazones has been developed. This method avoids the direct use of diazo compounds and allows the synthesis of structurally diverse azines. An azine was further found to exhibit strong yellow fluorescence and shows promise as a reagent for biological imaging.