Copper(I)‐catalyzed reaction of unsymmetrical alkyne with HB(pin): a density functional theory study |
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Authors: | Yan Li |
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Institution: | School of Petroleum and Chemical Engineering, Dalian University of Technology, Panjin City, Liaoning Province, China |
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Abstract: | With the aid of density functional theory calculations, we have investigated the mechanism of copper(I)‐catalyzed reaction between unsymmetrical alkyne 1‐phenyl‐1‐butyne and HB(pin). The results of the density functional theory calculations show that the reaction mechanism involves syn‐addition of catalyst (NHC]CuH) (NHC = N‐heterocyclic carbene) to 1‐phenyl‐1‐butyne to form the alkenyl copper intermediates 2a and 5a , and then intermediates 2a and 5a react with HB(pin) to give intermediates 3 ( 3a , 3b ) and 6 ( 6a , 6b ), and finally elimination of catalyst completes the catalytic cycle and yields the α‐product P1 and β‐product P2 . We found that α‐product should be more favored than β‐product. The calculated results are consistent with the experimental findings. The present paper may provide a useful guide for understanding other analogous copper‐catalyzed hydroboration of unsymmetrical alkynes. |
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Keywords: | HB(pin) potential energy surface (PES) reaction mechanism theoretical calculations unsymmetrical alkyne |
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