A metal-free annulation reaction of β-acylamino ketone derivatives has been reported for the synthesis of a group of functionalized spirooxazolines and oxazolines in good to excellent yields. The reaction proceeds via phenyliodine(III) diacetate (PIDA)-mediated oxidative C–O bond formation in the presence of BF₃–OEt₂. The mild reaction conditions, broad substrate scope, simple execution and synthetic potential of the products make this novel protocol very attractive.

中文翻译：

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β-酰基氨基酮的无金属环化：通过氧化C–O键的形成容易地获得螺恶唑啉和恶唑啉

已经报道了β-酰基氨基酮衍生物的无金属环化反应，用于合成一组官能化的螺恶唑啉和恶唑啉，收率好至极好。反应在存在BF ₃ -OEt ₂的情况下通过二乙酸苯基碘（III）（PIDA）介导的氧化C-O键进行。温和的反应条件，广泛的底物范围，简单的操作方法和产品的合成潜力使这种新颖的方案非常有吸引力。