established that a cyclopentadienyl RhIII complex with two phenyl groups and a pendant amide moiety catalyzes the formal Lossen rearrangement/[3+2] annulation cascade of N‐pivaloyl benzamides and acrylamides with alkynes leading to substituted indoles and pyrroles. Mechanistic studies revealed that this cascade reaction proceeds via not the Lossen rearrangement to form anilides or enamides but C−H bond cleavage
precursors in reactions with thioethers under the catalysis of a commercially available Ru(II) complex, from which a variety of sulfimides were synthesized efficiently and mildly. If an allyl group is contained in the thioether precursor, the [2,3]-sigmatropic rearrangement of the sulfimide occurs simultaneously and the N-allyl-N-(thio)amides were obtained as the final products. Preliminary mechanistic studies
Lossen rearrangement by Rh(<scp>iii</scp>)-catalyzed C–H activation/annulation of aryl hydroxamates with alkynes: access to quinolone-containing amino acid derivatives
作者:Dmitry A. Petropavlovskikh、Daria V. Vorobyeva、Ivan A. Godovikov、Sergey E. Nefedov、Oleg A. Filippov、Sergey N. Osipov
DOI:10.1039/d1ob01711j
日期:——
convenient and robust method for the preparation of new CF3-containing 2-quinolones has been developed via a Rh(III)-catalyzed C–H activation/Lossenrearrangement/annulation cascade of N-pivaloyloxy-arylamides with internal alkynes bearing an α-CF3-α-amino acid moiety on the triple bond. This work expands the scope of valuable products that are available through C–H activation/annulation reactions of
通过Rh( III )催化的C-H活化/ Lossen重排/环化级联N-新戊酰氧基-芳基酰胺与内部带有α三键上的-CF 3 -α-氨基酸部分。这项工作扩大了通过芳基酰胺在有机合成中的 C-H 活化/环化反应可获得的有价值产品的范围。
Rhodium-Catalyzed CH Alkynylation of Arenes at Room Temperature
作者:Chao Feng、Teck-Peng Loh
DOI:10.1002/anie.201309198
日期:2014.3.3
The rhodium(III)‐catalyzed ortho CH alkynylation of non‐electronically activated arenes is disclosed. This process features a straightforward and highly effective protocol for the synthesis of functionalized alkynes and represents the first example of merging a hypervalent iodine reagent with rhodium(III) catalysis. Notably, this reaction proceeds at room temperature, tolerates a variety of functional
An efficient synthesis of 2,5-disubstitutedoxazolesvia Co(III) catalysis is described herein. The synthesis is achieved under mild conditions through [3+2] cycloaddition of N-pivaloyloxyamides and alkynes. The reaction operates through an internal oxidation pathway and features a very broad substrate scope. The one-step synthesis of natural products such as texamine and balsoxin has been demonstrated