It is possible to say that zeolites are the most widely used catalysts in industry They are crystalline microporous materials which have become extremely successful as catalysts for oil refining, petrochemistry, and organic synthesis in the production of fine and speciality chemicals, particularly when dealing with molecules having kinetic diameters below 10 A The reason for their success in catalysis is related to the following specific features of these materials:1 (1) They have very high surface area and adsorption capacity (2) The adsorption properties of the zeolites can be controlled, and they can be varied from hydrophobic to hydrophilic type materials (3) Active sites, such as acid sites for instance, can be generated in the framework and their strength and concentration can be tailored for a particular application (4) The sizes of their channels and cavities are in the range typical for many molecules of interest (5-12 A), and the strong electric fields2 existing in those micropores together with an electronic confinement of the guest molecules3 are responsible for a preactivation of the reactants (5) Their intricate channel structure allows the zeolites to present different types of shape selectivity, ie, product, reactant, and transition state, which can be used to direct a given catalytic reaction toward the desired product avoiding undesired side reactions (6) All of these properties of zeolites, which are of paramount importance in catalysis and make them attractive choices for the types of processes listed above, are ultimately dependent on the thermal and hydrothermal stability of these materials In the case of zeolites, they can be activated to produce very stable materials not just resistant to heat and steam but also to chemical attacks Avelino Corma Canos was born in Moncofar, Spain, in 1951 He studied chemistry at the Universidad de Valencia (1967−1973) and received his PhD at the Universidad Complutense de Madrid in 1976 He became director of the Instituto de Tecnologia Quimica (UPV-CSIC) at the Universidad Politecnica de Valencia in 1990 His current research field is zeolites as catalysts, covering aspects of synthesis, characterization and reactivity in acid−base and redox catalysis A Corma has written about 250 articles on these subjects in international journals, three books, and a number of reviews and book chapters He is a member of the Editorial Board of Zeolites, Catalysis Review Science and Engineering, Catalysis Letters, Applied Catalysis, Journal of Molecular Catalysis, Research Trends, CaTTech, and Journal of the Chemical Society, Chemical Communications A Corma is coauthor of 20 patents, five of them being for commercial applications He has been awarded with the Dupont Award on new materials (1995), and the Spanish National Award “Leonardo Torres Quevedo” on Technology Research (1996) 2373 Chem Rev 1997, 97, 2373−2419

From Microporous to Mesoporous Molecular-Sieve Materials and Their Use in Catalysis

Efficient and reliable amplification of chirality has borne its greatest fruit with transition metal-catalyzed reactions since enantiocontrol may often be imposed by replacing an achiral or chiral racemic ligand with one that is chiral and scalemic While the most thoroughly developed enantioselective transition metal-catalyzed reactions are those involving transfer of oxygen (epoxidation and dihydroxylation)1,2 and molecular hydrogen,3 the focus of this review is on the area of enantioselective transition metal-catalyzed allylic alkylations which may involve C-C as well as C-X (X ) H or heteroatom) bond formation4-9 The synthetic utility of transitionmetal-catalyzed allylic alkylations has been soundly demonstrated since its introduction nearly three decades ago10-21 In contrast to processes where the allyl moiety acts as the nucleophilic partner, we will limit our discussion to processes which result in nucleophilic displacements on allylic substrates (eq 1) Such reactions have been recorded with a broad

http://web4.uwindsor.ca/users/j/jlichaa/reference.nsf/0/10ff8b04ff3a317885256d88005720f6/$FILE/cr-1996-96-395-allylpd-asym.pdf

Asymmetric Transition Metal-Catalyzed Allylic Alkylations.

Homochiral Metal–Organic Frameworks for Asymmetric Heterogeneous Catalysis

5.7. [32π + 32σ] Cycloadditions 74 5.8. [44π + 22π] Cycloadditions 75 6. Seven-Membered Ring Formation 78 6.1. [44π + 32σ] Cycloadditions 78 6.2. [52π+2σ + 22π] Cycloadditions 79 7. Eight-Membered Ring Formation 79 7.1. [22π + 22π + 22π + 22π] Cycloadditions 80 7.2. [44π + 22π + 22π] Cycloadditions 80 7.3. [44π + 44π] Cycloadditions 81 7.4. [66π + 22π] Cycloadditions 83 8. Ten-Membered Ring Formation 85 9. Conclusion and Remarks 87

Transition Metal-Mediated Cycloaddition Reactions

C–H activation has surfaced as an increasingly powerful tool for molecular sciences, with notable applications to material sciences, crop protection, drug discovery, and pharmaceutical industries, among others. Despite major advances, the vast majority of these C–H functionalizations required precious 4d or 5d transition metal catalysts. Given the cost-effective and sustainable nature of earth-abundant first row transition metals, the development of less toxic, inexpensive 3d metal catalysts for C–H activation has gained considerable recent momentum as a significantly more environmentally-benign and economically-attractive alternative. Herein, we provide a comprehensive overview on first row transition metal catalysts for C–H activation until summer 2018.

3d Transition Metals for C-H Activation.

need to be sulfonated in order to produce the stable polysemiquinone form of the polymer. Indeed, additional sulfonation and consequent protonation of amine nitrogen atoms would convert some of the -(NH)to -(NHzf)groups and hence destabilize the polymer by reducing the extent of its T conjugation. The absorption maxima at 1080, 700, and 620 cm-' in the FTIR spectrum of compound IIIA,B are consistent with the presence9 of SO3groups attached to the aromatic rings. The absorption maxima at 820 and 870 cm-I indicative of 1,2,4-trisubstitution of the rings are out-of-plane bending of aromatic hydrogens. These absorptions are not present in the 1,2-disubstituted emeraldine base ( I I ) , from which compound IIIA,B was synthesized. The solubilities of compounds IIIA,B and IV differ markedly from those of the corresponding protonated and nonprotonated forms, respectively, of parent polyaniline. Compound IIIA,B dissolves appreciably in aqueous 0.1 M N H 4 0 H or NaOH to give the corresponding salts whereas emeraldine hydrochloride when treated in this manner is converted to the insoluble emeraldine base form (11). The anionic (SO,-) groups are presumably largely responsible for its solubility in water. Compound IIIA,B partly dissolves in DMSO, giving the dark green color of the protonated polyaniline, but is apparently deprotonated when it dissolves in N-methyl-2-pyrrolidinone (NMP), in which it has a blue-violet color, characteristic of compound IV. The high concentration of protons in the vicinity of the polymer backbone due to the presence of the attached SO3groups is not only responsible for the retention of doping of the polymer at the higher pH values, where the parent emeraldine base polymer (TI) is essentially a (nondoped) insulator, but is also consistent with the observed faster electrochemical redox reactions of compound IIIA,B in aqueous media.

Enantioselective Epoxidation of Unfunctionalized Olefins Catalyzed by (salen)Manganese Complexes

Highly enantioselective epoxidation catalysts derived from 1,2-diaminocyclohexane

A practical method is described for the asymmetric epoxidation of cis-β-methylstyrene by commercial bleach with up to 86% ee

Wei Zhang

Papers

Enantioselective Epoxidation of Unfunctionalized Olefins Catalyzed by (salen)Manganese Complexes

Highly enantioselective epoxidation catalysts derived from 1,2-diaminocyclohexane

Asymmetric olefin epoxidation with sodium hypochlorite catalyzed by easily prepared chiral manganese(III) salen complexes

Electronic tuning of asymmetric catalysts

Highly Enantioselective, Low-Temperature Epoxidation of Styrene