ABSTRACT
A method for the facile synthesis of ethene-bridged terthiophenes (EBTTs) in two steps has been developed. The first step is a double Sonogashira coupling between 3',4'-dibromo-2,2':5',2â³-terthiophene and terminal alkynes to give dialkynylated terthiophenes, and the second step is a cyclization reaction to afford EBTTs. The fundamental physical properties of EBTTs were also studied.
ABSTRACT
Palladium-catalyzed domino C-H/N-H functionalization for the synthesis of novel nitrogen-bridged thienoacenes and 10H-benzo[4,5]thieno[3,2-b]indole derivatives from dihaloarene is reported. This domino sequence consists of initial C-H functionalization of the benzo[b]thiophene moiety, followed by Buchwald-Hartwig coupling. This transformation is also useful for the synthesis of highly π-extended compounds.
ABSTRACT
Site-selective sequential coupling reactions directed toward bis(diaryl)butadiynes are described. The reaction site could be controlled completely by the on/off application of electricity. The electro-oxidative homo-coupling of terminal alkynes (electricity ON) and the subsequent Suzuki-Miyaura coupling (electricity OFF) afforded bis(diaryl)butadiynes in high yields. The obtained 1,4-bis(diaryl)butadiynes could be converted to a 2,5-bis(diaryl)thiophene derivative, which exhibited blue fluorescence.
