Wang, Yun-Peng; Fang, Kun; Tu, Yong-Qiang; Yin, Jun-Jie; Zhao, Qi; Ke, Tian published their research in Nature Communications on December 31 ,2022. The article was titled 《An efficient approach to angular tricyclic molecular architecture via Nazarov-like cyclization and double ring-expansion cascade》.Category: esters-buliding-blocks The article contains the following contents:
A modular and efficient method for constructing angular tri-carbocyclic architectures containing quaternary carbon center(s), e.g., I (R = Me) from 1,3-dicycloalkylidenyl ketones, e.g., II is established, which involves an unconventional synergistic cascade of a Nazarov cyclization and two ring expansions. It features high selectivity, mild conditions and convenient operation, wide scope and easy availability of substrate. Substitution at the 4πe-system with electron-donating group favors this reaction, while that with electron-withdrawing group or proton disfavors. The electron-donating group directs the initial ring expansion at its own site, while the p-π- or n-π- associated substituent favors selectively the later ring expansion near its location because of the beneficial maintenance of an original conjugated system. The stereoselectivity has proved to be governed by either the steric effect at the expanded rings, or the migration ability of the migrating atom. D. Functional Theory calculation suggests that the initial Nazarov cyclization would be the rate-determining step. A racemic total synthesis of the natural (±)-waihoensene is realized in 18 steps by use of this methodol. In the experiment, the researchers used many compounds, for example, Methyl 3-oxovalerate(cas: 30414-53-0Category: esters-buliding-blocks)
Methyl 3-oxovalerate(cas: 30414-53-0) belongs to ketone compounds. Ketone compounds have important physiological properties. They are found in several sugars and in compounds for medicinal use, including natural and synthetic steroid hormones. Molecules of the anti-inflammatory agent cortisone contain three ketone groups.Category: esters-buliding-blocks
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics