Synthesis of Diarylamines in the Thiophene Series by Buchwald-Hartwig Coupling­

Abstract

We describe here the palladium-catalyzed amination of polysubstituted bromothiophenes under mild conditions (using Cs₂CO₃ as base). Anilines bearing electron-donating groups gave good results whereas anilines with electron-withdrawing substituents required greater catalyst loadings and gave lower yields.

Key words

palladium catalysis - amination - bromothiophenes - di­arylamines

References

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11

Aminothiophenes were synthesized as described in ref. 7.