TY - JOUR
T1 - Overcoming Selectivity Issues in Reversible Catalysis: A Transfer Hydrocyanation Exhibiting High Kinetic Control
AU - Bhawal, Benjamin N.
AU - Reisenbauer, Julia C.
AU - Ehinger, Christian
AU - Morandi, Bill
N1 - Funding Information:
This project received funding from the European Research Council under the European Union’s Horizon 2020 research and innovation program (Shuttle Cat, Project ID: 757608). We also thank the Max-Planck-Society and ETH Zürich for support. We are also grateful to Prof. B. List for sharing analytical equipment. B.N.B. acknowledges the Leverhulme Trust and the ERC for funding. J.C.R. acknowledges a fellowship of the Stipendienfonds Schweizerische Chemische Industrie (SSCI). We thank Prof. Z. K. Wickens (UW–Madison) and Prof. R. H. Grubbs (CalTech) for helpful discussions.
Publisher Copyright:
Copyright © 2020 American Chemical Society.
PY - 2020/6/24
Y1 - 2020/6/24
N2 - Reversible catalytic reactions operate under thermodynamic control, and thus, establishing a selective catalytic system poses a considerable challenge. Herein, we report a reversible transfer hydrocyanation protocol that exhibits high selectivity for the thermodynamically less favorable branched isomer. Selectivity is achieved by exploiting the lower barrier for C-CN oxidative addition and reductive elimination at benzylic positions in the absence of a cocatalytic Lewis acid. Through the design of a novel type of HCN donor, a practical, branched-selective, HCN-free transfer hydrocyanation was realized. The synthetically useful resolution of a mixture of branched and linear nitrile isomers was also demonstrated to underline the value of reversible and selective transfer reactions. In a broader context, this work demonstrates that high kinetic selectivity can be achieved in reversible transfer reactions, thus opening new horizons for their synthetic applications.
AB - Reversible catalytic reactions operate under thermodynamic control, and thus, establishing a selective catalytic system poses a considerable challenge. Herein, we report a reversible transfer hydrocyanation protocol that exhibits high selectivity for the thermodynamically less favorable branched isomer. Selectivity is achieved by exploiting the lower barrier for C-CN oxidative addition and reductive elimination at benzylic positions in the absence of a cocatalytic Lewis acid. Through the design of a novel type of HCN donor, a practical, branched-selective, HCN-free transfer hydrocyanation was realized. The synthetically useful resolution of a mixture of branched and linear nitrile isomers was also demonstrated to underline the value of reversible and selective transfer reactions. In a broader context, this work demonstrates that high kinetic selectivity can be achieved in reversible transfer reactions, thus opening new horizons for their synthetic applications.
U2 - 10.1021/jacs.0c03184
DO - 10.1021/jacs.0c03184
M3 - Article
C2 - 32478515
AN - SCOPUS:85087094205
SN - 0002-7863
VL - 142
SP - 10914
EP - 10920
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 25
ER -