A new and efficient method for palladium(II) catalytic desulfitative conjugate addition of arylsulfinic acids with α,β-unsaturated carbonyl compound has been developed. The key reacting intermediates including aryl Pd(II) sulfinic intermediate, aryl Pd(II), and C═O—Pd complexes were captured by ESI-MS/MS, which provide new experimental evidence for the understanding of addition mechanism.
Visible Light-Catalyzed Cascade Radical Cyclization of <i>N</i>-Propargylindoles with Acyl Chlorides for the Synthesis of 2-Acyl-9<i>H</i>-pyrrolo[1,2-<i>a</i>]indoles
tandem radical cyclization of N-propargylindoles with acyl chlorides for accessing 2-acyl-9H-pyrrolo[1,2-a]indoles is established. This transformation involves sequential addition of the acyl radical to the carbon-carbon triple bond, intramolecular cyclization with the 2-position of indole, and isomerization of the carbon-carbon double bond. The experimental results show that this reaction contains
method with high efficiency for the synthesis of α,β-unsaturated amides from the easily prepared propargyl alcohols and TMSN3 using TMSCl as an acid promoter is developed. A wide variety of α,β-unsaturated amides were produced in moderate to excellent yields. Mechanistic studies indicate that this transformation involves TMSCl-mediated allenylazide intermediate formation, C–C bond cleavage, and C–N
Synthesis of arylated chalcone derivatives via palladium cross-coupling reactions
作者:Rafaela G.M. da Costa、Francisco R.L. Farias、Davi Back、Jones Limberger
DOI:10.1016/j.tetlet.2018.01.038
日期:2018.2
reported. The protocol begins with the Heck reaction between chalcones and aryl iodides providing β-arylchalcones. This reaction tolerates various functional groups on both rings, as well as deactivated aryl iodides. The products are obtained in moderate to excellent yields and the (E)-β-arylchalcones (E:Z > 96:4) can be isolated via precipitation. Competitive Heck reactions pointed to a significant effect
Decatungstate as a direct hydrogen atom transfer photocatalyst for synthesis of trifluromethylthioesters from aldehydes
作者:Xiaochen Wang、Jianyang Dong、Yuxiu Liu、Hongjian Song、Qingmin Wang
DOI:10.1016/j.cclet.2021.03.070
日期:2021.10
We have developed a versatile, mild protocol for trifluoromethylthiolation reactions of aldehydes with catalysis by a decatungstate hydrogen atom transfer photocatalyst under redox-neutral conditions. The protocol is highly selective, operationally simple, and compatible with a wide array of sensitive functional groups. It can be used for late-stage functionalization of bioactive molecules, which makes