Palladium‐Catalyzed Branch‐ and Z‐Selective Allylic C−H Amination with Aromatic Amines

Abstract

Allylamines are important building blocks in the synthesis of bioactive compounds. The direct coupling of allylic C−H bonds and commonly available amines is a major synthetic challenge. An allylic C−H amination of 1,4‐dienes has been accomplished by palladium catalysis. With aromatic amines, branch‐selective allylic aminations are favored to generate thermodynamically unstable Z‐allylamines. In addition, more basic aliphatic cyclic amines can also engage in the reaction, but linear dienyl allylic amines are the major products.

Functional Liquid Crystal Elastomers Based on Dynamic Covalent Chemistry

“…The classical polysiloxane elastomer is widely recognized for its excellent adaptability and mechanical strength, and arises thanks to its Si−O−Si backbone, [31a,32, 104] which also contributes to significantly lowering its glass transition temperature compared to that of the C−C polymeric skeleton [73] . Indeed, this ancient chemistry has also revealed unique dynamic exchange reactions, [105] such as silyl ether metathesis and the acid‐ and base‐catalyzed equilibration of siloxanes (Scheme 3j–k).…”