Kumari Susheela, Maddipoti Karthik, Das Bidisa, Ray Saumi
Birla Institute of Technology and Science , Pilani , Rajasthan 333031 , India.
Technical Research Center , Indian Association for the Cultivation of Science , Jadavpur, Kolkata 700032 , India.
Inorg Chem. 2019 Jan 22;58(2):1527-1540. doi: 10.1021/acs.inorgchem.8b03031. Epub 2019 Jan 10.
A series of palladium complexes of tetradendate Schiff base ligands L1 ( N,N'-bis(salicylidene)phenylene-1,3-diamine) and its derivatives L2 and L3 have been synthesized by using the "flexible ligand method" within the supercage of zeolite-Y. These complexes in both their free and encapsulated states have been thoroughly characterized with the help of different characterization tools such as XRD, SEM-EDS, BET, thermal analysis, XPS, IR, and UV-vis spectroscopic studies. All these encapsulated complexes are identified with a dramatic red shift of the d-d transition in their electronic spectra when compared with their free states. Theoretical as well as experimental studies together suggest a substantial modification of the structural parameters of square planar Pd(II)-Schiff base complexes upon encapsulation within the supercage of zeolite-Y. Encapsulated complexes are also subject to show modified catalytic activities toward the Heck reaction. These heterogeneous catalysts can easily be separated from the reaction mixture and reused.
通过“柔性配体法”在Y型沸石的超笼内合成了一系列四齿席夫碱配体L1（N，N'-双（水杨醛）亚苯基-1,3-二胺）及其衍生物L2和L3的钯配合物。借助不同的表征工具，如XRD、SEM-EDS、BET、热分析、XPS、IR和UV-vis光谱研究，对这些处于游离态和包封态的配合物进行了全面表征。与游离态相比，所有这些包封的配合物在其电子光谱中均表现出d-d跃迁的显著红移。理论和实验研究共同表明，当在Y型沸石的超笼内包封时，平面正方形Pd（II）-席夫碱配合物的结构参数会发生实质性改变。包封的配合物对Heck反应也表现出改性的催化活性。这些多相催化剂可以很容易地从反应混合物中分离出来并重复使用。
