Diverse cyclization catalyzed by In(OTf)3 for the convergent assembly of substituted tetrahydrofurans and tetrahydropyrans.
[reaction: see text]. A novel In(OTf)3-catalyzed (3,5) oxonium-ene type cyclization for the facile construction of various multisubstituted tetrahydrofurans and tetrahydropyrans was successfully developed. Further mechanistic investigations unveiled an In(OTf)3-catalyzed skeletal reorganization of the tetrahydrofuran to its thermodynamic isomer under thermal conditions.
Loh
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Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543. chmlphtp@nus.edu.sg
Hu
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QY
Tan
K T
KT
Cheng
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HS