The selective activation of inert C-H bonds has emerged as a promising tool for avoiding wasteful traditional coupling reactions. Oxidative coupling of simple aromatics allows for a cost-effective synthesis of biaryls. The utilization of this technology is however severely hampered by a poor regioselectivity and by the limited stability of state of the art homogeneous Pd catalysts. Here we show that confinement of cationic Pd in the pores of a zeolite allows for a shape-selective C-H activation of simple aromatics without functional handle or electronic bias. For instance, out of 6 possible isomers, 4,4'-bitolyl is produced with high shape-selectivity (80 %) in oxidative toluene coupling on Pd-Beta. Not only is a robust, heterogeneous catalytic system obtained; a concept is also set to control the selectivity in transition metal catalyzed arene C-H activation by spatial confinement in zeolite pores. MainBiarylic bonds are important structural motifs in numerous organic chemicals. Their current industrial production relies on traditional coupling reactions (Suzuki, Ullmann etc.), which use pre-activated arenes (aryl halides, arylboronic acids etc.) 1 . The high cost of these intermediates and the associated waste generation usually direct their application towards high-end, specialty chemicals. Especially in the polymer industry there is a growing demand for biarylic monomers because of their superior chemical and physical stability, and their favorable health and safety profiles 2,3,4 . Direct functionalization of unreactive C-H bonds via transition metal mediated C-H activation has emerged as a promising alternative to traditional multi-step approaches 1 . C-H/C-H arene-arene couplings can in principle be used for the direct synthesis of biaryls from simple arenes, with e.g. Pd carboxylates as the catalysts 6,7,8,9,10 . If O2 is used as the oxidant, water is the only by-product 11 . Unfortunately, the multitude of C-H bonds present in organic reactants, and the poor differentiation between them often result in poor regioselectivity. Consequently, reactions with simple arenes (e.g. toluene) lead to useless mixtures of many isomers 12 . Ortho-selectivity can be achieved if the existing substituent exerts a directing effect, as is typical for ketone groups, carbamates, amides

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The oxidative carbonylation of N-protected indoles was investigated to directly synthesize indole-3-carboxylic acids. Using Rh(III)-zeolites as heterogeneous catalysts, the single-site Rh-species reach unprecedented activities (> 100 turnovers), while the metal...

Electrophilic amination has emerged as a more environmentally benign approach to construct arene C−N bonds. However, heterogeneous catalysts remain largely unexplored in this area, even though their use could facilitate product purification and catalyst recovery. Here we investigate strategies to heterogenize a Cu(2,2′-bipyridine) catalyst for the amination of arenes lacking a directing group with hydroxylamine-O-sulfonic acid (HOSA). Besides immobilization of Cu on a metal−organic framework (MOF) or covalent organic framework (COF) with embedded 2,2′-bipyridines, a ship-in-a-bottle approach was followed in which the Cu complex is encapsulated in the pores of a zeolite. Recyclability and hot centrifugation tests show that zeolite Betaentrapped Cu II (2,2′-bipyridine) is superior in terms of stability. With N-methylmorpholine as a weakly coordinating, weak base, simple arenes, such as mesitylene, could be aminated with yields up to 59%, corresponding to a catalyst TON of 24. The zeolite could be used in three consecutive runs without a decrease in activity. Characterization of the catalyst by EPR and XAS showed that the active catalytic complex consisted of a site-isolated Cu II species with one 2,2′-bipyridine ligand.

Hydroisomerisation of n‐butane to isobutane is a challenging reaction, even for Pt‐loaded zeolites with strong acid sites. In comparison with 10‐membered ring (10MR) zeolites, 12‐membered ring (12MR) zeolites give consistently higher isomerisation yields. We report that besides the known catalysts with *BEA topology, also three‐dimensional frameworks with MSE and YFI topologies (with Si/Al∼10) are suitable to obtain high isobutane selectivities and yields. As an alternative to Beta zeolites obtained via templated synthesis, Beta zeolites prepared via a template‐free synthesis proved to be more active at lower temperatures and delivered higher isobutane yields in such conditions. Side reactions such as the Pt‐catalysed hydrogenolysis were successfully suppressed by decreasing the Pt content, even in hydrogen‐rich conditions. Isobutane yields up to 31 % were achieved in a single pass.