Shou-Guo Wang

Bio: Shou-Guo Wang is an academic researcher from Chinese Academy of Sciences. The author has contributed to research in topics: Enantioselective synthesis & Catalysis. The author has an hindex of 16, co-authored 28 publications receiving 1289 citations. Previous affiliations of Shou-Guo Wang include École Polytechnique & École Polytechnique Fédérale de Lausanne.

Catalytic Enantioselective Transformations Involving C-H Bond Cleavage by Transition-Metal Complexes.

Abstract: The development of new methods for the direct functionalization of unactivated C–H bonds is ushering in a paradigm shift in the field of retrosynthetic analysis. In particular, the catalytic enantioselective functionalization of C–H bonds represents a highly atom- and step-economic approach toward the generation of structural complexity. However, as a result of their ubiquity and low reactivity, controlling both the chemo- and stereoselectivity of such processes constitutes a significant challenge. Herein we comprehensively review all asymmetric transition-metal-catalyzed methodologies that are believed to proceed via an inner-sphere-type mechanism, with an emphasis on the nature of stereochemistry generation. Our analysis serves to document the considerable and rapid progress within in the field, while also highlighting limitations of current methods.

Asymmetric Dearomatization of β-Naphthols through an Amination Reaction Catalyzed by a Chiral Phosphoric Acid†

Abstract: A highly efficient catalytic asymmetric dearomatization of naphthols by means of an electrophilic amination reaction catalyzed by chiral phosphoric acid is presented. This protocol provides a facile access to functionalized β-naphthalenone compounds with a chiral quaternary carbon center in excellent yields and enantioselectivity (up to 99 % yield, up to 96 % ee).

Asymmetric Dearomatization of β‐Naphthols through a Bifunctional‐Thiourea‐Catalyzed Michael Reaction

Abstract: An intermolecular asymmetric dearomatization reaction of β-naphthols with nitroethylene through a chiral-thiourea-catalyzed Michael reaction is described. Enantioenriched functionalized β-naphthalenones with an all-carbon quaternary stereogenic center could thus be easily constructed from simple naphthol derivatives in good yields and excellent enantioselectivity (up to 79% yield, 98% ee).

Organocatalytic asymmetric chlorinative dearomatization of naphthols

Abstract: An organocatalytic asymmetric chlorinative dearomatization of naphthols was realized for the first time, providing chiral naphthalenones with a Cl-containing all-substituted stereocenter in excellent yields and enantioselectivity (up to 97% yield and 96% ee). The reaction features mild reaction conditions, good tolerance of diverse functional groups and simple reaction operation.

3d Transition Metals for C-H Activation.

Abstract: 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.

Catalytic asymmetric dearomatization (CADA) reactions of phenol and aniline derivatives

Abstract: Phenols are widely used as starting materials in both industrial and academic society. Dearomatization reactions of phenols provide an efficient way to construct highly functionalized cyclohexadienones. The main challenge to make them asymmetric by catalytic methods is to control the selectivity while overcoming the loss of aromaticity. In this tutorial review, an up to date summary of recent progress in CADA reactions of phenol and aniline derivatives is presented.

Enantioselective C(sp3)‒H bond activation by chiral transition metal catalysts.

Abstract: BACKGROUND The ultimate goal of synthetic chemistry is the efficient assembly of molecules from readily available starting materials with minimal waste generation. The synthesis of organic molecules—compounds containing multiple carbon-hydrogen (C–H) and carbon-heteroatom (such as oxygen or nitrogen) bonds—has greatly improved our quality of life. Pharmaceuticals that can treat disease, agrochemicals that enhance crop yields, and materials used in computer engineering are but three illustrative examples. And yet more often than not, the syntheses of these substances have proved challenging because of restrictions on how molecules can be constructed. Major advances in organic chemistry have relied on the discovery of reactions that dramatically altered chemists’ approach to building molecules. Canonical organic reactions typically rely on the high reactivity of functional groups (with respect to a C–H bond) in order to introduce new functionality in a target molecule. However, there are times when the accessibility of certain functional groups at particular carbon centers may be restricted; in these cases, the installation of functionality may require several steps and can lead to undesired side reactions, delaying the production of as well as decreasing the overall yield of a synthetic target. Considering that organic molecules possess an abundance of C–H bonds, it should be unsurprising that C–H functionalization (the conversion of C–H bonds into C–X bonds, where X ≠ H) has garnered considerable attention as a technique that could alter synthetic organic chemistry by enabling relatively unreactive C–H bonds to be viewed as dormant functionality. And yet, to date applications of C–H functionalization logic are hindered by considerable limitations in terms of regioselectivity and stereoselectivity (the construction of chiral centers). ADVANCES Although numerous approaches to regioselective C–H functionalization have been extensively reported, only recently has attention been placed on addressing the issues of stereoselectivity. One such solution entails chiral transition metal catalysts in which a metal complexed to a chiral ligand reacts directly with a C–H bond, forming a chiral organometallic intermediate that is then diversely functionalized. A variety of transition metal catalysts have been shown to affect the asymmetric metallation of C–H bonds of enantiotopic carbons (C–H bonds on different carbons) or enantiotopic protons (C–H bonds on the same carbon). The major driving force behind the development of enantioselective C–H activation has been the design of chiral ligands that bind to transition metals, creating a reactive chiral catalyst while also increasing the reactivity at the metal center, accelerating the rate of C–H activation. OUTLOOK In order for enantioselective C–H activation to become a standard disconnection in asymmetric syntheses, the efficiency of catalyses and breadth of transformations must be improved. Although the specific requirements to achieve these goals are unclear, we argue that improved ligand design will be instrumental to further progress until any C–H bond of any molecule can be converted into any functionality in high yields with high enantioselectivity. The impact of such progress will no doubt have rippling effects in seemingly disparate fields, such as medicine, by enabling the syntheses of previously inaccessible forms of matter.

Electrocatalytic C–H Activation

Abstract: C–H activation has emerged as a transformative tool in molecular synthesis, but until recently oxidative C–H activations have largely involved the use of stoichiometric amounts of expensive and toxic metal oxidants, compromising the overall sustainable nature of C–H activation chemistry. In sharp contrast, electrochemical C–H activation has been identified as a more efficient strategy that exploits storable electricity in place of byproduct-generating chemical reagents. Thus, transition-metal catalysts were shown to enable versatile C–H activation reactions in a sustainable manner. While palladium catalysis set the stage for C(sp2)–H and C(sp3)–H functionalizations by N-containing directing groups, rhodium and ruthenium catalysts allowed the use of weakly coordinating amides and acids. In contrast to these precious 4d transition metals, the recent year has witnessed the emergence of versatile cobalt catalysts for C–H oxygenations, C–H nitrogenations, and C–C-forming [4+2] alkyne annulations. Thereby, the ...