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
Rhodium(III)-Catalyzed C–H Activation and Annulation with 1-Alkynylphosphine Sulfides: A Mild and Regioselective Access for the Synthesis of Bulky Phosphine Ligands
作者:Bin Li、Jie Yang、Hong Xu、Haibin Song、Baiquan Wang
DOI:10.1021/acs.joc.5b02265
日期:2015.12.18
We reported herein rhodium(III)-catalyzed C–H activation and annulation reactions for the synthesis of bulky phosphine ligands by using 1-alkynylphosphine sulfides as key starting materials. In the presence of [Cp*RhCl2]2 (5 mol %) and CsOAc (2.0 equiv), various N-(pivaloyloxy)benzamides (3.0 equiv) could react smoothly with 1-alkynylphosphine sulfides at 40 °C in MeOH/CF3CH2OH cosolvent without external
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
Rhodium(III)-Catalyzed C–H Activation/Annulation with Vinyl Esters as an Acetylene Equivalent
作者:Nicola J. Webb、Stephen P. Marsden、Steven A. Raw
DOI:10.1021/ol502095z
日期:2014.9.19
The behavior of electron-richalkenes in rhodium-catalyzed C–H activation/annulation reactions is investigated. Vinyl acetate emerges as a convenient acetylene equivalent, facilitating the synthesis of sixteen 3,4-unsubstituted isoquinolones, as well as select heteroaryl-fused pyridones. The complementary regiochemical preferences of enol ethers versus enol esters/enamides is discussed.
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。