The Preparation of Trisubstituted Alkenyl Nucleoside Phosphonates under Ultrasound-Assisted Olefin Cross-Metathesis
摘要:
Intermolecular ultrasound-assisted olefin cross-metathesis is reported. This approach allows an easy access to challenging trisubstituted alkenyl nucleoside phosphonates. Regioselective chemoenzymatic deacetylation and Mitsunobu coupling are also described.
Assembly of Terpenoid Cores by a Simple, Tunable Strategy
作者:Ouidad Lahtigui、Fabien Emmetiere、Wei Zhang、Liban Jirmo、Samira Toledo-Roy、John C. Hershberger、Jocelyn M. Macho、Alexander J. Grenning
DOI:10.1002/anie.201608863
日期:2016.12.19
Oxygenated, polycyclic terpenoid natural products have important biological activities. Although total synthesis of such terpenes is widely studied, synthetic strategies that allow for controlled placement of oxygen atoms and other functionality remains a challenge. Herein, we present a simple, scalable, and tunable synthetic strategy to assemble terpenoid‐like polycycloalkanes from cycloalkanones
Fe-Catalyzed Hydroalkylation of Olefins with <i>para</i>-Quinone Methides
作者:Yangyong Shen、Jifeng Qi、Zhenjun Mao、Sunliang Cui
DOI:10.1021/acs.orglett.6b01173
日期:2016.6.3
A novel Fe-catalyzed hydroalkylation of olefins with para-quinone methides (p-QMs) for accessing phenols has been developed. In this protocol, various olefins could convert to alkyl radicals and undergo addition to para-quinone methides toward C–C bond formation and aromatization. The reaction conditions are mild and the substrate scopes are broad.
Complex Hydroindoles by an Intramolecular Nitrile-Intercepted Allylic Alkylation Cascade Reaction
作者:Peter Vertesaljai、Ion Ghiviriga、Alexander J. Grenning
DOI:10.1021/acs.orglett.8b00499
日期:2018.4.6
Bisnucleophilic reagents derived from malononitrile, ketones, benzaldehydes, and nitromethane can react with bisallylic electrophiles via a nitrile-intercepted allylic alkylation cascade reaction to yield complex hydroindole architectures. Also noteworthy is that the only stoichiometric byproducts from the preparation and reaction of the bisnucleophile and biselectrophile are water, acetic acid, and
The synthesis of two new Huperzine A analogues is reported. Both products present an amino substituted benzo-fused system in place of the pyridone ring of the natural alkaloid. The synthetic strategy to the two analogues is based on three different key palladium-catalyzed steps, namely a carbonylation reaction, an epoxide isomerization and a bicycloannulation reaction.