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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Asymmetric Synthesis of Hydrodibenzofurans from Norcaradienes: Kinetic Resolution via [3 + 2] Cycloaddition with
Siyuan Wang1, Lichao Ning1, Zhiqiang Li1
1Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
Abstract:
The catalytic asymmetric [3 + 2] cycloaddition of racemic norcaradienes with quinones to construct multicyclic hydrodibenzofurans was achieved by the use of chiral N,N'-dioxide/metal complex catalysts. Kinetic resolution of norcaradienes accompanied by partial racemization occurred, and one enantiomer in prior acted as the C2 synthon to participate in diastereoselective cycloaddition. An enantiodivergent synthesis via a switch of metal ions was observed when naphthoquinone was used as the partner. DFT calculations revealed the profiles of the cycloaddition processes.
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