alkyne metathesis will always be the little brother of alkene metathesis, it allows problems to be solved that are currently beyond reach of the more famous sibling. This notion is exemplified by the tulearin macrolides, which could only be selectively forged by ring‐closing alkyne metathesis (RCAM)/trans reduction using the latest generation of alkyne metathesis catalysts.
No heteroatom required! In many solid-phase syntheses, after the release from the polymer support a heteroatom (e.g. O, S, N) remains in the substrate as a residue of a linking protecting group. With polymer-bound tin reagents cleavage and cyclization of the substrate with C-C bond formation (see picture) can now be achieved by intramolecular Stille coupling. S=substrate.
1,3-Diynes compound 7a protected the corticosterone-injured PC12 cells through regulation of the apoptosis related proteins and exerted antidepressant effect in mice forced swim test in a concentration-dependent manner.
Modular terpene synthesis enabled by mild electrochemical couplings
作者:Stephen J. Harwood、Maximilian D. Palkowitz、Cara N. Gannett、Paulo Perez、Zhen Yao、Lijie Sun、Héctor D. Abruña、Scott L. Anderson、Phil S. Baran
DOI:10.1126/science.abn1395
日期:2022.2.18
biosynthesis is a case study of how the logic of a modular design can lead to diverse structures with unparalleled efficiency. This work leverages modern nickel-catalyzed electrochemical sp 2 –sp 3 decarboxylativecoupling reactions, enabled by silver nanoparticle–modified electrodes, to intuitively assemble terpene natural products and complex polyenes by using simple modular building blocks. The step change
Facile Preparation of Spirolactones by an Alkoxycarbonyl Radical Cyclization–Cross‐Coupling Cascade
作者:Nicholas A. Weires、Yuriy Slutskyy、Larry E. Overman
DOI:10.1002/anie.201903353
日期:2019.6.17
An alkoxycarbonyl radical cyclization–cross‐couplingcascade has been developed that allows functionalized γ‐butyrolactones to be prepared in one step from simple tertiary alcohol‐derived homoallylic oxalate precursors. The reaction succeeds with aryl and vinyl electrophiles and is compatible with heterocyclic fragments in both coupling partners. This chemistry allows for the rapid construction of