Work

Beyond Wittig Olefination: Phosphorus Ylide as a Ring-Expansion Reagent for Dibenzocycloheptanone Synthesis

Year: 2025

Type: article

Abstract: We report an unprecedented transformation between phenanthrene-9,10-diones and phosphorus ylide, where methylenetriphenylphosphane exhibits dual reactivity patterns, enabling both olefination and ring expansion to construct seven-membered carbocycles in moderate to good yields. This process proceeds through initial Wittig olefination followed by an unusual alkenyl group 1,2-migration pathway from either an oxaphosphetane or betaine intermediate. Mechanistic studies, including deuterium-labeling experiments and isolation of key intermediates, support a pathway involving conformationally controlled ring expansion.

Source: JACS Au

DOI: 10.1021/jacsau.5c01138

Authors: Lin Li, Haozhe Zha, Xiaoping Xue, Longhui Duan, Zhenhua Gu

Institutions: University of Science and Technology of China, Hefei National Center for Physical Sciences at Nanoscale, Henan Agricultural University, Nanjing University

Language: English

Topic: Phosphorus compounds and reactions

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $3,500

Funders: National Natural Science Foundation of China, Nanjing University, National Key Research and Development Program of China