NHC-copper-thiophene-2-carboxylate complex for the hydroboration of terminal alkynes
Won Jun Jang1, Byung-Nam Kang, Ji Hun Lee
1Department of Chemistry, Sungkyunkwan University, Suwon 16419, Korea. jaesook@skku.edu.
Abstract:
An air-stable N-heterocyclic carbene-copper thiophene-2-carboxylate (CuTC) complex has been prepared for the stereoselective hydroboration of terminal alkynes using pinacolborane (HBpin) or 1,8-naphthalenediaminatoborane (HBdan). The newly synthesized complex can be directly activated by hydroboranes without a cocatalyst such as a base, and exhibits high reactivity for the hydroboration of alkynes under mild conditions. A gram-scale hydroboration of terminal phenylacetylene demonstrated the applicability of the copper complex for the preparation of alkenyl boronates.
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Termination of Translation


