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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Programmed Synthesis of Tetra-Aryl Thiophenes with Stepwise, Ester-Controlled Regioselectivity
Cynthia Messina1, Xavier Ottenwaelder1, Pat Forgione1
1Department of Chemistry and Biochemistry, Concordia University, Montreal, Quebec H4B 1R6, Canada.
Abstract:
Herein, we report a modular synthetic route to access tetra-arylated thiophene compounds with four different substituents with programmed chemical control provided by an ester activating/directing group. This method enables the functionalization of individual positions of thiophene sequentially via regioselective halogenations and cross-coupling reactions. The reaction sequence described provides tetra-arylated thiophenes in higher yields than previous routes and employs practical reaction protocols, simple catalytic systems, and short reaction times.
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