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UiO-66 is regarded as an epitome of metal-organic frameworks (MOFs) because of its stability. Defect engineering has been used as a toolbox to alter the performance of MOFs. UiO-66 is among the most widely explored MOFs because of its capability to bear a high number of defects without undergoing structural collapse. Several representative works in the field of MOF-based defect engineering are available based on UiO-66. In this review, more emphasis is given toward the construction of catalytic sites by engineering defects in UiO-66 as a representative including all the detailed synthesis procedures for inducing defects, and the characterization techniques used to analyze these defects in UiO-66 are discussed. Furthermore, a comprehensive review for the defects themselves and the support using defects in catalysis is provided to accentuate the importance of defect engineering.

[EN] Heterogeneous single-site catalysts consist of isolated, well-defined, active sites that are spatially separated in a given solid and, ideally, structurally identical. In this review, the potential of metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) as platforms for the development of heterogeneous single-site catalysts is reviewed thoroughly. In the first part of this article, synthetic strategies and progress in the implementation of such sites in these two classes of materials are discussed. Because these solids are excellent playgrounds to allow a better understanding of catalytic functions, we highlight the most important recent advances in the modelling and spectroscopic characterization of single-site catalysts based on these materials. Finally, we discuss the potential of MOFs as materials in which several single-site catalytic functions can be combined within one framework along with their potential as powerful enzyme-mimicking materials. The review is wrapped up with our personal vision on future research directions., S. M. J. Rogge, J. Hajek, and V. Van Speybroeck acknowledge the Fund for Scientific Research - Flanders (FWO), the Research Board of Ghent University (BOF) and BELSPO in the frame of IAP/7/05 for financial support. V. Van Speybroeck acknowledges funding from the European Union's Horizon 2020 research and innovation programme (consolidator ERC grant agreement no. 647755 - DYNPOR (2015-2020)). This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 641887 (project acronym: DEFNET). W. Dewitte and C. Caratelli are acknowledged for technical support with the figures. J. Gascon acknowledges funding from the European Union's 2020 research and innovation programme (ERC grant agreement no. 335746 - CrystEng-MOF-MMM) and from the Dutch Organization for Scientific Research (NWO, VIDI grant agreement 723.012.107 - MetMOFCat).

[Abstract] A sequential one-pot indium-catalyzed intramolecular hydroarylation (IMHA) of bromopropargyl aryl ethers and amines, and palladium-catalyzed cross-coupling reaction using triorganoindium reagents (R3In) has been developed. In this transformation, the IMHA of 3-bromo-2-propynyl aryl ethers under indium(III) catalysis, proceeds regioselectively through a 6-endo dig pathway to afford 4-bromo-2Hchromenes. Subsequent palladium-catalyzed cross-coupling with R3In gives 4-substituted-2H-chromenes in one-pot. This sequential transformation was extended to 3-bromo-2-propynyl-N-tosylanilines to afford 4-substituted-1,2-dihydroquinolines. The dual-catalyzed procedure takes place efficiently with a variety of propargyl aryl ethers and amines and R3In (R = aryl, heteroaryl, alkyl or alkynyl), showing the efficiency of these organometallics and proving the compatibility of indium and palladium in catalysis. Ministerio de Economía y Competividad; CTQ2015-68369-P Xunta de Galicia. Consellería de Cultura, Educación e Ordenación Universitaria; GRC2014/042

An overview of asymmetric transformations induced by photochemical means in the presence of a substoichiometric amount of external chiral reagent is presented. The main obstacles in achieving asymmetric induction catalytically, and successful examples of ways to overcome these hurdles are discussed.

In this article, we review the recent progress that has been made in the field of Lewis-acid catalysis of carbon carbon-bond-forming reactions in aqueous solution. Since water hampers the hard hard interactions between the catalyst and the reactant, it often complicates catalysis. However, once coordination has taken place, water can have beneficial effects on rates and selectivities of Lewis acid catalysed Diels Alder reactions, aldol reactions, allylation reactions, Barbier and Mannich type reactions as well as Michael additions.

Homoadamantene is readily converted by Lewis-acid catalysa into a single major product 2- methyladamantane. 1 However, the behaviour of the 4-homoadamantyl cation generated from homoadamantene(1) and 4-homoadamantano1(2) by concentrated sulphuric acid in the presence of pentane was quite different! Instead of one, three major products (90-95% by glc) were formed in the ratio 2:l:l. Almost identical products distribution was obtained from both 1 and 2. 3 Two 1 minor components were identified as homoadamantane ($ and 2-methyladamantane (5) by H nmr. ir, and mass spectra, and glc comparison with authentic samples.