In this paper we describe the facile and straightforward covalent functionalization of commercially available dendritic poly(propylenimine) and hyper‐branched poly(ethylenimine) with P‐containing functional groups. The P‐functionalized macromolecules have been applied as multivalent ligands in the Pd‐catalyzed allylic substitution reactions (batch and continuous process) using either morpholine or thiophenol as nucleophile. Palladium complexes of all described molecules are active in allylic substitution reactions. The PEI functionalized polymers appear more sensitive to small changes in the P/Pd ratio than the PPI analogues, but form catalysts that are more active. When used in a continuous flow process the macromolecules are completely retained by the nanofiltration membrane, while the catalytic activity decreases with time because of palladium depletion. This is more severe for the allylic thiolation, probably because of the stronger affinity of sulfur for palladium, facilitating palladium leaching.
This study presents the development of a mechanochemical protocol for a charge-accelerated aza-Claisen rearrangement. The protocol waives the use of commonly applied transition metals, ligands, or pyrophoric Lewis acids, e.g., AlMe3. Based on (heterocyclic) tertiary allylamines and acyl chlorides, the desired tertiary amides were prepared in yields ranging from 17% to 84%. Moreover, the same protocol was applied for a Belluš–Claisen-type rearrangement resulting in the synthesis of a 9-membered lactam without further optimization.