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![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Carbene-Catalyzed Desymmetric Amidation Enables Modular Access to Planar Chiral Thioureas and Imides
Jia-Le Sheng1, Bei-Bei Jin1, Ze-Qi Xia1
1Key Laboratory of Green and Precise Synthetic Chemistry and Applications, Ministry of Education; Anhui Provincial Key Laboratory of Synthetic Chemistry and Applications; School of Chemistry and Chemical Engineering, Huaibei Normal University, Huaibei, Anhui 235000, P. R. China.
Abstract:
Planar chiral [2.2]paracyclophanes (PCPs) have found wide applications in organic synthesis, ranging from chiral functional materials to catalysts and ligands. Herein, an N-heterocyclic carbene-catalyzed amidation is reported for the efficient construction of planar chiral PCP derivatives. Structurally diverse planar chiral thioureas and imides were delivered in good to excellent enantioselectivities. Mechanistic studies indicate that the desymmetrization process plays a vital role in the enantioselectivity control. Downstream functionalization further enriched the structural diversity of PCPs.
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