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 plausibly undergoes an S_N2 substitution mechanism via an α-C-bound hypervalent iodine intermediate. The diastereoselectivity of the reaction mainly originates from thermodynamic control.

中文翻译：

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高价碘介导的环酮的非对映选择性α-乙酰氧基化。

发现包含高价碘（III）试剂和BF ₃ •OEt ₂路易斯酸的二元杂化体系对于环酮的非对映选择性α-乙酰氧基化有效。在该杂化体系中，BF ₃ •OEt ₂路易斯酸可激活高价碘（III）试剂和环状酮，从而实现平稳的α-乙酰氧基化反应，从而实现高非对映选择性。这种高价碘介导的环酮反应的α-乙酰氧基化可能通过α-经历了S _N 2取代机制。C结合的高价碘中间体。反应的非对映选择性主要来自热力学控制。