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Research on the chemoselective metal‐catalyzed hydrogenation of conjugated π‐systems has mostly been focussed on enones. Herein, we communicate the understudied asymmetric hydrogenation of enimines catalyzed by N,P‐iridium complexes and chemoselective toward the alkene. A number of enoxime ethers underwent hydrogenation smoothly to yield the desired products in high yield and stereopurity (up to 99 % yield, up to 99 % ee). No hydrogenation of the C=N π‐bond was observed under the applied reaction conditions (20 bar H2, rt, DCM). It was demonstrated that the chiral oxime ether could be hydrolyzed into the ketone with complete preservation of the installed stereogenity at the α‐carbon. At last, a binding mode of the substrate to the active iridium catalyst and the consequence for the stereoselective outcome was proposed. [ABSTRACT FROM AUTHOR]

A silver-promoted radical mechanism is proposed for this reaction. [ABSTRACT FROM AUTHOR]

The scalable hydrogenation of vinylic, allylic, and homoallylic sulfones is investigated with the conversion of the E-isomers being faster than the one of Z-isomers while delivering opposite enantiomers. [ABSTRACT FROM AUTHOR]

The highly efficient hydrogenation of various unsaturated cyclic and acyclic sulfones in the presence of IRC coupled with Ramberg-Baecklund rearrangement offers a novel access to the target compounds. [ABSTRACT FROM AUTHOR]