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Regio- and enantioselective hydroformylation of styrenes is attained upon embedding a chiral Rh complex in a nonchiral supramolecular cage formed from coordination-driven self-assembly of macrocyclic dipalladium complexes and tetracarboxylate zinc porphyrins. The resulting supramolecular catalyst converts styrene derivatives into aldehyde products with much higher chiral induction in comparison to the nonencapsulated Rh catalyst. Spectroscopic analysis shows that encapsulation does not change the electronic properties of the catalyst nor its first coordination sphere. Instead, enhanced enantioselectivity is rationalized by the modification of the second coordination sphere occurring upon catalyst inclusion inside the cage, being one of the few examples in achieving an enantioselective outcome via indirect through-space control of the chirality around the catalyst center. This effect resembles those taking place in enzymatic sites, where structural constraints imposed by the enzyme cavity can impart stereoselectivities that cannot be attained in bulk. These results are a showcase for the future development of asymmetric catalysis by using size-tunable supramolecular capsules We thank the European Research Council (ERC-2011-StG- 277801 to X.R., ERC-2009-StG-239910 to M.C., and ERC- 2013-AdG-339782-NAT_CAT to J.N.H.R.), the Spanish MINECO (Consolider-Ingenio CSD2010-00065, INNPLANTA project INP-2011-0059-PCT-420000-ACT1, and CTQ2012-32436), and the Catalan DIUE of the Generalitat de Catalunya (2009SGR637 and PhD grant to C.G.S.)

A non-heme iron complex that catalyzes highly enantioselective epoxidation of olefins with H2O2 is described. Improvement of enantiomeric excesses is attained by the use of catalytic amounts of carboxylic acid additives. Electronic effects imposed by the ligand on the iron center are shown to synergistically cooperate with catalytic amounts of carboxylic acids in promoting efficient O-O cleavage and creating highly chemo-and enantioselective epoxidizing species which provide a broad range of epoxides in synthetically valuable yields and short reaction times We acknowledge financial support from European Research Council (ERC-2009-StG-239910), MINECO of Spain (CTQ2012-37420-C02-01/BQU, Consolider-Ingenio CSD2010-00065), and the Catalan DIUE of the Generalitat de Catalunya (2009SGR637). J.Ll.-F. thanks MICINN for a RyC contract. X.R. and M.C. acknowledge ICREA-Academia awards. X.R. is grateful for financial support from INNPLAN-TA Project No. IPN-2011-0059-PCT-42000-ACT1. I.G.-B. thanks the European Community for an IOF Marie Curie fellowship. We acknowledge STRs from UdG for technical support

Copper-catalyzed halide exchange reactions under very mild reaction conditions are described for the first time using a family of model aryl halide substrates. All combinations of halide exchange (I, Br, Cl, F) are observed using catalytic amounts of CuI. Strikingly, quantitative fluorination of aryl–X substrates is also achieved catalytically at room temperature, using common F– sources, via the intermediacy of aryl–CuIII–X species. Experimental and computational data support a redox CuI/CuIII catalytic cycle involving aryl–X oxidative addition at the CuI center, followed by halide exchange and reductive elimination steps. Additionally, defluorination of the aryl–F model system can be also achieved with CuI at room temperature operating under a CuI/CuIII redox pai We thank Prof. S. S. Stahl (Univ. of Wisconsin, Madison, WI) for fruitful comments and for early experiments conducted by A.C. in Stahl's lab. We acknowledge financial support from MICINN of Spain (CTQ2009-08464/BQU to M.C., CTQ2008-03077/BQU and CTQ2011-23156/BQU to M.S., Consolider-Ingenio CSD2010-00065, and Ph.D. grant to A.C.), European Research Council for Project ERC-2011-StG-277801 and the Catalan DIUE of the Generalitat de Catalunya (2009SGR637 to M.S., and a Ph.D. grant to M. Canta). X.R, MC., and MS. thank ICREA-Academia awards. We thank STR's from UdG for technical support, and we also acknowledge the Centre de Serveis Cientifics i Academics de Catalunya (CESCA) for partial funding of computer time

Au has been demonstrated to mediate a number of organic transformations through the utilization of its π Lewis acid character, Au(I)/Au(III) redox properties or a combination of both. As a result of the high oxidation potential of the Au(I)/Au(III) couple, redox catalysis involving Au typically requires the use of a strong external oxidant. This study demonstrates unusual external oxidant-free Au(I)-catalyzed halide exchange (including fluorination) and Csp2-O bond formation reactions utilizing a model aryl halide macrocyclic substrate. Additionally, the halide exchange and Csp2-O coupling reactivity could also be extrapolated to substrates bearing a single chelating group, providing further insight into the reaction mechanism. This work provides the first examples of external oxidant-free Au(I)-catalyzed carbon-heteroatom cross-coupling reactions This work was supported by grants from the European Research Council (Starting Grant Project ERC-2011-StG-277801), the Spanish MINECO (CTQ2013-43012-P, Consolider-Ingenio CSD2010-00065, INNPLANTA project INP-2011-0059-PCT- 420000-ACT1) and Generalitat de Catalunya (2014 SGR 862)

The [Pd(SIPr)(PCy3)] complex efficiently promotes a tandem process involving dehydrogenation of formic acid and hydrogenation of C-C multiple bonds using H-2 formed in situ. The isolation of a key catalytic hydridoformatopalladium species, [Pd{OC(O)H}(H)(IPr)(PCy3)], is reported. The complex plays a key role in the Pd(0)-mediated formation of hydrogen from formic acid. Mechanistic and computational studies delineate the operational role of the palladium complex in this efficient tandem sequence The EPSRC and the Royal Society (University Research Fellowship to C.S.J.C.), the Spanish MICINN (Ramon y Cajal Contract RYC-2009-05226 to A.P.), the EC (Career Integration Grant CIG09-GA-2011-293900 to A.P.), and Generalitat de Catalunya (BE Fellowship 2011BE100793 to A.P.) are acknowledged for financial support