Liu-Zhu Gong

Bio: Liu-Zhu Gong is an academic researcher from University of Science and Technology of China. The author has contributed to research in topics: Enantioselective synthesis & Aldol reaction. The author has an hindex of 29, co-authored 61 publications receiving 3340 citations. Previous affiliations of Liu-Zhu Gong include Chinese Academy of Sciences & Nankai University.

Novel Small Organic Molecules for a Highly Enantioselective Direct Aldol Reaction

Abstract: Novel organic molecules containing an l-proline amide moiety and a terminal hydroxyl for catalyzing direct asymmetric aldol reactions of aldehydes in neat acetone are designed and prepared. Catalyst 3d, prepared from l-proline and (1S,2S)-diphenyl-2-aminoethanol, exhibits high enantioselectivities of up to 93% ee for aromatic aldehydes and up to >99% ee for aliphatic aldehydes. A theoretical study of transition structures demonstrates the important role of the terminal hydroxyl group in the catalyst in the stereodiscrimination. Our results suggest a new strategy in the design of new organic catalysts for direct asymmetric aldol reactions and related transformations because plentiful chiral resources containing multi-hydrogen bond donors, for example, peptides, might be adopted in the design.

Highly Enantioselective Organocatalytic Biginelli Reaction

Abstract: A series of binol- and H8-binol-based phosphoric acids have for the first time been evaluated for their ability to catalyze Biginelli reactions of aldehydes, thiourea or urea, and β-keto esters. A new chiral phosphoric acid, derived from 3,3‘-diphenyl-H8-binol, exhibited superior catalytic activity and enantioselectivity compared to its structural analogues, affording high enantioselectivities ranging from 85 to 97% ee with a wide scope of substrates. A metal-free preparation of optically active monastrol was achieved on the basis of the current process.

Asymmetric Organocatalytic Three-Component 1,3-Dipolar Cycloaddition: Control of Stereochemistry via a Chiral Brønsted Acid Activated Dipole

Abstract: A Bronsted acid catalyzed three-component asymmetric 1,3-dipolar addition reaction between aldehydes, amino esters, and dipolarophiles by a new bisphosphoric acid, derived from the linked BINOL, furnished multiply substituted pyrrolidines in high yield with excellent enantioselectivities under mild conditions.

Highly enantioselective oxidative couplings of 2-naphthols catalyzed by chiral bimetallic oxovanadium complexes with either oxygen or air as oxidant.

Abstract: The chiral bimetallic oxovanadium complexes have been designed for the enantioselective oxidative coupling of 2-naphthols bearing various substituents at C6 and/or C7. The chirality transferring fr...

Chiral Brønsted acid-catalyzed direct asymmetric Mannich reaction.

Abstract: A chiral Bronsted acid-catalyzed direct asymmetric Mannich reaction has been described. Various phosphoric acids, prepared from BINOL and H8-BINOL derivatives, have been evaluated for catalyzing the direct Mannich reaction. In the presence of a truly catalytic amount of the phosphoric acid, anti-selective Mannich reactions of cyclic ketones with a wide scope of aldimines were obtained in high yields with excellent enantioselectivities (up to 98% ee) and high diastereomeric ratios (up to 98/2 dr). A one-pot Mannich reaction using aromatic ketones as donors proceeded smoothly to give β-amino carbonyls with fairly good enantioselectivities.

Asymmetric catalysis by chiral hydrogen-bond donors.

Abstract: Hydrogen bonding is responsible for the structure of much of the world around us. The unusual and complex properties of bulk water, the ability of proteins to fold into stable three-dimensional structures, the fidelity of DNA base pairing, and the binding of ligands to receptors are among the manifestations of this ubiquitous noncovalent interaction. In addition to its primacy as a structural determinant, hydrogen bonding plays a crucial functional role in catalysis. Hydrogen bonding to an electrophile serves to decrease the electron density of this species, activating it toward nucleophilic attack. This principle is employed frequently by Nature's catalysts, enzymes, for the acceleration of a wide range of chemical processes. Recently, organic chemists have begun to appreciate the tremendous potential offered by hydrogen bonding as a mechanism for electrophile activation in small-molecule, synthetic catalyst systems. In particular, chiral hydrogen-bond donors have emerged as a broadly applicable class of catalysts for enantioselective synthesis. This review documents these advances, emphasizing the structural and mechanistic features that contribute to high enantioselectivity in hydrogen-bond-mediated catalytic processes.

Bond Formations between Two Nucleophiles: Transition Metal Catalyzed Oxidative Cross-Coupling Reactions

Abstract: 3.1. C-M and X-H as Nucleophiles 1806 3.2. C-H and X-M as Nucleophiles 1809 3.2.1. C-Halogen Bond Formations 1809 3.2.2. C-O Bond Formations 1812 3.3. C-H and X-H as Nucleophiles 1812 3.3.1. C-O Bond Formations 1812 3.3.2. C-N Bond Formations 1815 4. Oxidative X-X Bond Formations between Two Nucleophiles 1819 5. Conclusions 1819 Author Information 1819 Biographies 1819 Acknowledgment 1820 References 1820