Synthesis of 2,3-disubstituted thiophenes from ketoalkynes

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2013
Vatansever, Erol Can
Synthesis of thiophene containing compounds are of particular interest in synthetic organic chemistry. Besides the importance for synthetic organic chemistry, thiophene derivatives are used in applied research such as drug synthesis and study of functional materials. In this thesis, a new methodology for developing of 2,3-disubstituted thiophenes was developed. This methodology utilizes readily available compounds in a two-step synthesis to provide a facile access to the 2,3-disubstituted thiophenes. In the first step, ketoalkynes were prepared by Sonogashira coupling of readily available acyl chlorides and terminal alkynes. Then they were reacted with 2,5-dihydroxy-1,4-dithiane in the presence of triethylamine to yield alcohol intermediates. Finally, alcohol intermediates were dehydrated by treatment with silica gel to yield 2,3-disubstituted thiophenes.

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Citation Formats
E. C. Vatansever, “Synthesis of 2,3-disubstituted thiophenes from ketoalkynes,” M.S. - Master of Science, Middle East Technical University, 2013.