In this work, we have developed an unconventional and highly enantioselective solvent-promoted Rauhut-Currier cyclization of enal-tethered cyclohexadienone by exploiting the reactivity of a simple Jørgensen-Hayashi catalyst through the merging of iminium and enamine activation. This asymmetric desymmetrization reaction has broad substrate scope in good yields with high to excellent enantioselectivity. DFT calculations suggest that the elimination of the alkoxy group is the rate-limiting step and that it proceeds through proton abstraction by solvent instead of a direct 1,3-proton shift.
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Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400 076, India.
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School of Chemistry and Chemical Engineering, Key Laboratory of the Colloid and Interface Chemistry, Ministry of Education, Shandong University, Jinan 250100, China.
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Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
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School of Chemistry, and Xi'an Key Laboratory of Sustainable Energy Materials Chemistry, Xi'an Jiaotong University, Xi'an 710049, P.R. China.
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Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India.
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