Cobalt-Catalyzed Chemoselective Transfer Hydrogenative Cyclization Cascade of Enone-Tethered Aldehydes
Shuang-Shuang Ma, Biao-Ling Jiang, Zheng-Kun Yu, Suo-Jiang Zhang and Bao-Hua Xu*
*Institution of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China, Email: bhxuipe.ac.cn
S.-S. Ma, B.-L. Jiang, Z.-K. Yu, S.-J. Zhang, B.-H. Xu, Org. Lett., 2021, 23, 3873-3878.
DOI: 10.1021/acs.orglett.1c00992 (free Supporting Information)
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The use of i-PrOH as environmentally benign hydrogen surrogate enables a ligand-free Co-catalyzed chemoselective reductive cyclization cascade of enone-tethered aldehydes. The selectivity between Michael-Aldol cycloreduction cascade and oxa-Michael cascade can be adjusted by the addition of TEMPO as a steric Lewis bases to provide 1H-indenes and dihydroisobenzofurans, respectively.
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