Synthesis of Benzo-Fused Cyclic Ketones via Metal-Free Ring Expansion of Cyclopropanols Enabled by Proton-Coupled Electron Transfer

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(18) The relative configuration of 3z was determined by X-ray crystallographic analysis of the corresponding hydrazone deriva- tive. Crystallographic data have been deposited with the Cam- bridge Crystallographic Data Centre database (http://www.ccdc.cam.ac.uk/) under code CCDC 2084574. For de- tails, see Supporting Information.

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