biostudies-literaturePiacentini PHorizon 2020 Framework Programmee202208014https://www.ebi.ac.uk/biostudies/studies/S-EPMC9543877biostudies-literatureUnknown61(36)Benzocycloheptenes constitute a common structural motif embedded in many natural products and biologically active compounds. Herein, we report their concise preparation from non-activated polycyclic arenes using a two-step sequence involving dearomative [4+2]-cycloaddition with arenophile in combination with palladium-catalyzed cyclopropanation, followed by cycloreversion-initiated ring expansion. The described strategy provides a working alternative to the Buchner reaction, which is limited to monocyclic arenes. Overall, this methylene-insertion molecular editing approach enables rapid and direct conversion of simple (hetero)arenes into a range of substituted (aza)benzocycloheptatrienes, which can undergo a myriad of downstream functionalizations.Angewandte Chemie (International ed. in English)Dearomative Ring Expansion of Polycyclic Arenes.PMC9543877804583Sarlah DPiacentini PBingham TWfalseDearomative Ring Expansion of Polycyclic Arenes.Benzocycloheptenes constitute a common structural motif embedded in many natural products and biologically active compounds. Herein, we report their concise preparation from non-activated polycyclic arenes using a two-step sequence involving dearomative [4+2]-cycloaddition with arenophile in combination with palladium-catalyzed cyclopropanation, followed by cycloreversion-initiated ring expansion. The described strategy provides a working alternative to the Buchner reaction, which is limited to monocyclic arenes. Overall, this methylene-insertion molecular editing approach enables rapid and direct conversion of simple (hetero)arenes into a range of substituted (aza)benzocycloheptatrienes, which can undergo a myriad of downstream functionalizations.2022-01-01T00:00:00Z2022 Sep2025-04-22T12:15:01.455Z2025-04-06T00:13:38.26ZS-EPMC95438773580286010.1002/anie.202208014