Urea-Functionalized Self-Assembled Molecular Prism for Heterogeneous Catalysis in Water Prodip Howlader Paramita Das Ennio Zangrando Partha Sarathi Mukherjee 10.1021/jacs.5b12237.s004 https://acs.figshare.com/articles/dataset/Urea_Functionalized_Self_Assembled_Molecular_Prism_for_Heterogeneous_Catalysis_in_Water/2072638 Reaction of a ditopic urea “strut” (<b>L</b><sub><b>1</b></sub>) with <i>cis</i>-(tmen)­Pd­(NO<sub>3</sub>)<sub>2</sub> yielded a [3+3] self-assembled molecular triangle (<b>T</b>) [<b>L</b><sub><b>1</b></sub> = 1,4-di­(4-pyridylureido)­benzene; tmen = <i>N,N,N′,N′</i>-tetramethylethane-1,2-diamine]. Replacing <i>cis</i>-(tmen)­Pd­(NO<sub>3</sub>)<sub>2</sub> in the above reaction with an equimolar mixture of Pd­(NO<sub>3</sub>)<sub>2</sub> and a clip-type donor (<b>L</b><sub><b>2</b></sub>) yielded a template-free multicomponent 3D trigonal prism (<b>P</b>) decorated with multiple urea moieties [<b>L</b><sub><b>2</b></sub> = 3,3′-(1<i>H</i>-1,2,4-triazole-3,5-diyl)­dipyridine]. This prism (<b>P</b>) was characterized by NMR spectroscopy, and the structure was confirmed by X-ray crystallography. The <b>P</b> was employed as an effective hydrogen-bond-donor catalyst for Michael reactions of a series of water-insoluble nitro-olefins in an aqueous medium. The <b>P</b> showed better catalytic activity compared to the urea-based ligand <b>L</b><sub><b>1</b></sub> and the triangle <b>T</b>. Moreover, the confined nanospace of <b>P</b> in addition to large product outlet windows makes this 3D architecture a perfect molecular vessel to catalyze Diels–Alder reactions of 9-hydroxymethylanthracene with N-substituted maleimide in the aqueous medium. The present results demonstrate new observations on catalytic aqueous Diels–Alder and Michael reactions in heterogeneous fashion employing a discrete 3D architecture of Pd­(II). The prism was recycled by simple filtration and reused several times without significant loss of activity. 2016-02-04 19:21:08 prism Pd product outlet windows ci Diel medium urea NMR 3 D architecture Michael reactions