聚酰胺-胺-2-吡啶甲醛席夫碱树枝状大分子钯配合物的制备、表征及催化性能

制备了聚酰胺-胺(PAMAM)-2-吡啶甲醛(Py)席夫碱树枝状大分子及其钯配合物。通过红外、核磁共振、元素分析、等离子耦合原子发散光谱及热重-差热等分析手段对其进行了结构确证。研究了PAMAM-2-吡啶甲醛席夫碱钯配合物在Heck反应中的催化性能。以三乙胺(Et₃N)作为缚酸剂,碘代苯(PhI):10 mmol,n(PhI):n(AA):n(Et₃N)为1:1.4:2.5,n(Pd)=6.1×10^-3 mmol(5.0G PAMAMPy-Pd),在5 mL DMF中,100 ℃和N₂气保护下反应25 min,产率90.1%。催化剂经过简单的过滤可回收,重复使用3次产率仍可达82.0%。

Preparation,Characterization and Catalytic Performance of Polyamidoamine-2-Pyridine Carbaldehyde Schiff Base Dendrimer Palladium Complexes

Polyamidoamine(PAMAM)-2-pyridine carbaldehyde(Py) Schiff base dendrimers and their palladium complexes were prepared. Their structures were characterized by FT-IR, elemental analysis, ICP and TG-DSC. Catalytic performance of these complexes in Heck reaction was investigated. PAMAM-2-pyridine carbaldehyde Schiff base dendrimer palladium complexes show better catalytic activity in DMF. Using triethylamine(Et₃N) as base, phenyliodide(PhI):10 mmol, n(PhI):n(AA):n(Et₃N)=1:1.4:2.5(AA:acylic acid), n(Pd)=6.1×10^-3 mmol(5.0G PAMAMPy-Pd). The yield is 90.1% with 100 ℃ and N₂ for 24 min in 5 mL DMF under above optimal conditions. These catalysts can be recovered by the simple filtration and solvent washing. The yield of product can reach up to 82.0% when the catalyst is used for the third time.