Supported Palladium–Gold Alloy Catalysts for Efficient and Selective Hydrosilylation under Mild Conditions with Isolated Single Palladium Atoms in Alloy Nanoparticles as the Main Active Site
Supported Pd–Au alloy catalysts were developed for the highly efficient and selective hydrosilylation of α,β-unsaturated ketones and alkynes. The Pd/Au atomic ratio of the Pd–Au alloy and the supporting material affected the catalytic activity, and supported Pd–Au alloy nanoparticles with a low Pd/Au atomic ratio functioned as highly active heterogeneouscatalystsundermildreactionconditions. Structural
Stereoselective synthesis of either (E)- or (Z)-silyl enol ether from the same acyclic α,β-unsaturated ketone using cationic rhodium complex-catalyzed 1,4-hydrosilylation
The stereoselective synthesis of either (E)- or (Z)-silyl enolether from the same acyclic α,β-unsaturated ketone is reported. Highly (Z)-selective conditions were the use of [Rh(cod)2]BF4/DPPE at roomtemperature with no solvent, whereas (E)-selective conditions were the use of [Rh(cod)2]BF4/P(1-Nap)3 (1-Nap = 1-naphthyl) under refluxing dichloromethane.
applied to a catalytic asymmetric nitrene-transfer reaction with enolsilylethers. The ruthenium catalyst was applicable to aliphatic enolsilylethers as well as aryl-containing enolsilylethers. The substrate scope of the ruthenium catalyst was superior to that of analogous chiral paddle-wheel rhodium catalysts. α-Amino ketonesderivedfrom aliphatic substrates were obtained in up to 97% ee with the
将手性桨轮双核钌催化剂应用于与烯醇甲硅烷基醚的催化不对称氮烯转移反应。钌催化剂适用于脂肪族烯醇硅醚以及含芳基的烯醇硅醚。钌催化剂的底物范围优于类似的手性桨轮铑催化剂。使用钌催化剂可获得高达 97% ee 的源自脂肪族底物的 α-氨基酮,而类似的铑催化剂仅产生适度的对映选择性。