3406-76-6Relevant articles and documents
Access to Spirocyclic Benzothiophenones with Multiple Stereocenters via an Organocatalytic Cascade Reaction
Formánek, Bed?ich,Tauchman, Ji?í,Císa?ová, Ivana,Vesely, Jan
, p. 8510 - 8521 (2020/07/16)
The present report describes an organocatalytic cascade reaction between 2-alkylidene benzo[b]thiophenone derivatives and enones in the presence of the Cinchona alkaloid amine. Spirobenzothiophenonic cyclohexane derivatives containing three stereocenters were prepared via one-step synthesis in yields ranging from 88 to 96% and in enantioselectivities (enantiomeric excess (ee)) ranging from 85 to 97%, with diastereoselectivities of approximately 14/2/1. Therefore, this method provides an efficient route for the synthesis of a new class of optically active 2-spirobenzothiophenones.
Compound, preparation method thereof, medical intermediate and application thereof
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Paragraph 0077-0084, (2020/08/06)
The invention relates to the technical field of chemical synthesis, and particularly discloses a compound, a preparation method thereof, a medical intermediate and an application thereof, the compoundcomprises the following raw materials: thioether, bromide and a proper amount of organic solvent, and the molar weight ratio of thioether to bromide is 1: (2-8). According to the compound provided bythe invention, thioether, bromide and a proper amount of organic solvent are used as raw materials, and the thioether compound can be obtained without adopting a catalyst, so that the problems of metal residues and the like are fundamentally eliminated, the provided preparation method is simple to operate, the method is simple in process and high in yield, the thioether compound is prepared through thioether metathesis reaction, metal catalysis is not needed in the whole reaction, meanwhile, the reaction condition is mild, the substrate range is wide, the problem of metal pollution existing in an existing thioether compound synthesis method is solved, and the method has wide market prospects in the fields of organic synthesis, medicine synthesis and the like.
Nucleophilic (Radio)Fluorination of Redox-Active Esters via Radical-Polar Crossover Enabled by Photoredox Catalysis
Webb, Eric W.,Park, John B.,Cole, Erin L.,Donnelly, David J.,Bonacorsi, Samuel J.,Ewing, William R.,Doyle, Abigail G.
supporting information, p. 9493 - 9500 (2020/05/18)
We report a redox-neutral method for nucleophilic fluorination of N-hydroxyphthalimide esters using an Ir photocatalyst under visible light irradiation. The method provides access to a broad range of aliphatic fluorides, including primary, secondary, and tertiary benzylic fluorides as well as unactivated tertiary fluorides, that are typically inaccessible by nucleophilic fluorination due to competing elimination. In addition, we show that the decarboxylative fluorination conditions are readily adapted to radiofluorination with [18F]KF. We propose that the reactions proceed by two electron transfers between the Ir catalyst and redox-active ester substrate to afford a carbocation intermediate that undergoes subsequent trapping by fluoride. Examples of trapping with O- and C-centered nucleophiles and deoxyfluorination via N-hydroxyphthalimidoyl oxalates are also presented, suggesting that this approach may offer a general blueprint for affecting redox-neutral SN1 substitutions under mild conditions.