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8.1.14.2.3 Variation 3: Alkoxy Directed ortho-Lithiation Groups

DOI: 10.1055/sos-SD-008-00213

Gribble, G. W.Science of Synthesis, (20068365.

The alkoxy group was one of the first directing groups to be recognized, as both Gilman and Wittig discovered this property of methoxy and other aryl ethers.[‌14‌,‌81‌,‌82‌] At least part of this property arises from the powerful inductive electron-withdrawing effect of oxygen that greatly acidifies ortho hydrogens. The myriad of natural products that contain methoxy groups often lend themselves to total synthesis via methoxy directed lithiation. A sampling of lithiated aryl ethers is shown in Scheme 11[‌83‌‌101‌] and an example of their use in Scheme 12 (e.g., to give 23).

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