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Hypervalent Iodine-Mediated Diastereoselective ?-Acetoxylation of Cyclic Ketones.

ABSTRACT: A binary hybrid system comprising a hypervalent iodine(III) reagent and BF3•OEt2 Lewis acid was found to be effective for the diastereoselective ?-acetoxylation of cyclic ketones. In this hybrid system, BF3•OEt2 Lewis acid allowed the activation of the hypervalent iodine(III) reagent and cyclic ketones for smooth ?-acetoxylation reaction, achieving high diastereoselectivity. This hypervalent iodine-mediated ?-acetoxylation of the cyclic ketone reaction plausibly undergoes an SN2 substitution mechanism via an ?-C-bound hypervalent iodine intermediate. The diastereoselectivity of the reaction mainly originates from thermodynamic control.

SUBMITTER: Tan J

PROVIDER: S-EPMC7365914 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Hypervalent Iodine-Mediated Diastereoselective α-Acetoxylation of Cyclic Ketones.

Tan Jiashen J Zhu Weiqin W Xu Weiping W Jing Yaru Y Ke Zhuofeng Z Liu Yan Y Maruoka Keiji K

Frontiers in chemistry 20200710

A binary hybrid system comprising a hypervalent iodine(III) reagent and BF3•OEt2 Lewis acid was found to be effective for the diastereoselective α-acetoxylation of cyclic ketones. In this hybrid system, BF3•OEt2 Lewis acid allowed the activation of the hypervalent iodine(III) reagent and cyclic ketones for smooth α-acetoxylation reaction, achieving high diastereoselectivity. This hypervalent iodine-mediated α-acetoxylation of the cyclic ketone reaction ...[more]

PMID: 32754572

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