5787-28-0Relevant articles and documents
Indene Derived Phosphorus-Thioether Ligands for the Ir-Catalyzed Asymmetric Hydrogenation of Olefins with Diverse Substitution Patterns and Different Functional Groups
Margalef, Jèssica,Biosca, Maria,de la Cruz-Sánchez, Pol,Caldentey, Xisco,Rodríguez-Escrich, Carles,Pàmies, Oscar,Pericàs, Miquel A.,Diéguez, Montserrat
supporting information, p. 4561 - 4574 (2021/04/05)
A family of phosphite/phosphinite-thioether ligands have been tested in the Ir-catalyzed asymmetric hydrogenation of a range of olefins (50 substrates in total). The presented ligands are synthesized in three steps from cheap indene and they are air-stable solids. Their modular architecture has been crucial to maximize the catalytic performance for each type of substrate. Improving most Ir-catalysts reported so far, this ligand family presents a broader substrate scope, covering different substitution patterns with different functional groups, ranging from unfunctionalized olefins, through olefins with poorly coordinative groups, to olefins with coordinative functional groups. α,β-Unsaturated acyclic and cyclic esters, ketones and amides werehydrogenated in enantioselectivities ranging from 83 to 99% ee. Enantioselectivities ranging from 91 to 98% ee were also achieved for challenging substrates such as unfunctionalized 1,1′-disubstituted olefins, functionalized tri- and 1,1′-disubstituted vinyl phosphonates, and β-cyclic enamides. The catalytic performance of the Ir-ligand assemblies was maintained when the environmentally benign 1,2-propylene carbonate was used as solvent. (Figure presented.).
Tandem Peterson olefination and chemoselective asymmetric hydrogenation of β-hydroxy silanes
Krajangsri, Suppachai,Wu, Haibo,Liu, Jianguo,Rabten, Wangchuk,Singh, Thishana,Andersson, Pher G.
, p. 3649 - 3653 (2019/03/28)
Here, we report the first Ir-N,P complex catalyzed tandem Peterson olefination and asymmetric hydrogenation of β-hydroxy silanes. This reaction resulted in the formation of chiral alkanes in high isolated yields (up to 99%) and excellent enantioselectivity (up to 99% ee) under mild conditions. Modification of the reaction conditions provides a choice to transform either an olefin or the β-hydroxy silane in a chemoselective manner. Additionally, based on this method, an expedient enantioselective synthesis of (S)-(+)-α-curcumene, from a simple ketone, was accomplished in two steps with 75% overall yield and 95% ee.
STEREORETENTIVE CROSS-COUPLING OF BORONIC ACIDS
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, (2018/11/21)
The present disclosure provides tri-orthoalkylphenyl phosphine catalysts that are tuned electrically and sterically. Method of using the catalyst for cross-coupling of unactivated secondary boronic acids with near-perfect levels of site- and stereoretention are also provided.
