2,2':5',2''-Terthiophene (α-Terthiophene) is an oligomer of the heterocycle thiophene. 2,2':5',2''-Terthiophene has been employed as building block for the organic semi-conductor polythiophene.
In the most common isomer of Terthiophene, two thienyl groups are connected via their 2 positions to a central thiophene, also at the carbon atoms flanking the sulfur.
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