3805-10-5Relevant articles and documents
Nitrone Formation by Reaction of an Enolate with a Nitro Group
Shimizu, Hiroaki,Yoshinaga, Kohei,Yokoshima, Satoshi
, p. 2704 - 2709 (2021/04/12)
Ketones with a 2-nitrophenyl group at the α-position were treated with sodium hydroxide in methanol at 60 °C. Under these conditions, enolates derived from the ketones intramolecularly reacted with the nitro group to form a variety of nitrones. Additional experimental results, including the unexpected isolation of N-hydroxyindolinone as a byproduct, led to a proposed reaction mechanism, occurring via an α-hydroxyketone. The resultant nitrones underwent inter- and intramolecular 1,3-dipolar cycloaddition with olefins to afford polycyclic isoxazolidines.
Intermetallic Nanocatalyst for Highly Active Heterogeneous Hydroformylation
Chen, Minda,Gupta, Geet,Ordonez, Claudio W.,Lamkins, Andrew R.,Ward, Charles J.,Abolafia, Celia A.,Zhang, Biying,Roling, Luke T.,Huang, Wenyu
supporting information, p. 20907 - 20915 (2021/12/14)
Hydroformylation is an imperative chemical process traditionally catalyzed by homogeneous catalysts. Designing a heterogeneous catalyst with high activity and selectivity in hydroformylation is challenging but essential to allow the convenient separation and recycling of precious catalysts. Here, we report the development of an outstanding catalyst for efficient heterogeneous hydroformylation, RhZn intermetallic nanoparticles. In the hydroformylation of styrene, it shows three times higher turnover frequency (3090 h-1) compared to the benchmark homogeneous Wilkinson's catalyst (966 h-1), as well as a high chemoselectivity toward aldehyde products. RhZn is active for a variety of olefin substrates and can be recycled without a significant loss of activity. Density functional theory calculations show that the RhZn surfaces reduce the binding strength of reaction intermediates and have lower hydroformylation activation energy barriers compared to pure Rh(111), leading to more favorable reaction energetics on RhZn. The calculations also predict potential catalyst design strategies to achieve high regioselectivity.
Expeditious Total Synthesis of Hemiasterlin through a Convergent Multicomponent Strategy and Its Use in Targeted Cancer Therapeutics
Carroll, Jason S.,Charoenpattarapreeda, Jiraborrirak,Spring, David R.,Walsh, Stephen J.
, p. 23045 - 23050 (2020/11/11)
Hemiasterlin is an antimitotic marine natural product with reported sub-nanomolar potency against several cancer cell lines. Herein, we describe an expeditious total synthesis of hemiasterlin featuring a four-component Ugi reaction (Ugi-4CR) as the key st