Palladium-Catalyzed Trifluoroethylation of Terminal Alkynes with 1,1,1-Trifluoro-2-iodoethane
摘要:
An efficient C-sp-CH2CF3 bond-forming reaction via Pd-catalyzed 2,2,2-trifluoroethylation of aryl and alkyl terminal alkynes has been developed. This protocol proceeds under mild conditions using the readily available and cheap reagent CF3CH2I as the source of the CH2CF3 group. Various terminal aryl alkynes as well as alkylacetylenes can be transformed Into the corresponding trifluoroethylated products In good-to-excellent yields. The method is tolerant of carbonyl, nitro, ester, cyano, and even formyl groups.
Trifluoromethylation of Propargylic Halides and Trifluoroacetates Using (Ph<sub>3</sub>P)<sub>3</sub>Cu(CF<sub>3</sub>) Reagent
作者:Tony S. N. Zhao、Kálmán J. Szabó
DOI:10.1021/ol3017287
日期:2012.8.3
A copper-mediatedtrifluoromethylation of propargylic halides and trifluoroacetates was performed with high allenyl or propargyl selectivity. The reaction proceeds smoothly with aliphatic and aromatic substituents bearing either electron-withdrawing or -supplying groups. Preliminary mechanistic results indicate an ionic mechanism involving nucleophilic transfer of the CF3 group from the Cu complex
Reactions of propargylic halides with trifluoromethyltrimethylsilane in the presence of a catalytic amount of copper(I) thiophene-2-carboxylate (CuTC) have been found to give the corresponding trifluoromethylated products in good to high yields with a high selectivity.
Copper-Catalyzed Decarboxylative Trifluoromethylation of Propargyl Bromodifluoroacetates
作者:Ryan Altman、Brett Ambler、Santosh Peddi
DOI:10.1055/s-0033-1339128
日期:——
The development of efficient methods for accessing fluorinated functional groups is desirable. Herein, we report a two-step method that utilizes catalytic copper for the decarboxylative trifluoromethylation of propargyl bromodifluoroacetates is described. This protocol affords a mixture of propargyl trifluoromethanes and trifluoromethyl allenes.
Cu-Catalyzed C–H Trifluoromethylation of 3-Arylprop-1-ynes for the Selective Construction of Allenic Csp<sup>2</sup>–CF<sub>3</sub> and Propargyl Csp<sup>3</sup>–CF<sub>3</sub> Bonds
A new method has been developed for the Cu-catalyzed C-H trifluoromethylation of 3-arylprop-1-ynes for the selective construction of allenic Csp(2)-CF3 and propargyl Csp(3)-CF3 bonds. The selective formation of allenic Csp(2)-CF3 and propargyl Csp(3)-CF3 bonds can be controlled by modifying the reaction conditions.