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Annulative π-Extension of Phospholes by Sequential Site-Selective C-H Iodination and Pd-Catalyzed C-H Coupling with
Ikki Kamiyoshi1, Shibo Xu2, Koji Hirano1,2
1Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
Abstract:
An annulative π-extension of the phospholes has been developed. The reaction system consists of site-selective C2-H iodination of the phosphole nucleus with in situ generated IOMs and Pd-catalyzed C-H coupling with internal alkynes. The developed sequential protocol is convenient to perform through simple filtration without purification of the iodinated intermediate. Thus, the highly π-extended phosphole derivatives can be readily prepared from easily accessible C2-H phospholes and alkynes. Preliminary optoelectronic characteristics of several newly obtained condensed phospholes are also described.
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