Expedient Synthesis of Substituted Thieno[3,2-b]thiophenes and Selenopheno[3,2-b]selenophenes Through Cascade
Yingqi Feng1, Xuelin Zhang1, Ziqing He1
1Jiangmen Key Laboratory of Synthetic Chemistry and Cleaner Production, School of Environmental & Chemical Engineering, Wuyi University, Jiangmen 529020, China.
Abstract:
Thieno[3,2-b]thiophenes are used as key components in optoelectronic materials, porous hydrogen-storage hosts, organic solar cells, and polymer semiconductors. A step-efficient synthetic protocol was proposed herein for obtaining multisubstituted thieno[3,2-b]thiophene and selenopheno[3,2-b]selenophenes in moderate to good yields via the bisulfur/biselenium cyclization of alkynyl diols with I2/Na2S2O3 or selenium. Using this strategy, substitution patterns were obtained for backbone modification in functional materials.
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