Complete Field Guide to Asymmetric BINOL-Phosphate Derived Brønsted Acid and Metal Catalysis: History and Classification by Mode of Activation; Brønsted Acidity, Hydrogen Bonding, Ion Pairing, and Metal Phosphates

Iron Catalysis in Organic Synthesis

Isatins As Privileged Molecules in Design and Synthesis of Spiro-Fused Cyclic Frameworks

Flow chemistry involves the use of channels or tubing to conduct a reaction in a continuous stream rather than in a flask Flow equipment provides chemists with unique control over reaction parameters enhancing reactivity or in some cases enabling new reactions This relatively young technology has received a remarkable amount of attention in the past decade with many reports on what can be done in flow Until recently, however, the question, “Should we do this in flow?” has merely been an afterthought This review introduces readers to the basic principles and fundamentals of flow chemistry and critically discusses recent flow chemistry accounts

The Hitchhiker's Guide to Flow Chemistry

The legacy of Gilbert Newton Lewis (1875-1946) pervades the lexicon of chemical bonding and reactivity. The power of his concept of donor-acceptor bonding is evident in the eponymous foundations of electron-pair acceptors (Lewis acids) and donors (Lewis bases). Lewis recognized that acids are not restricted to those substances that contain hydrogen (Bronsted acids), and helped overthrow the "modern cult of the proton". His discovery ushered in the use of Lewis acids as reagents and catalysts for organic reactions. However, in recent years, the recognition that Lewis bases can also serve in this capacity has grown enormously. Most importantly, it has become increasingly apparent that the behavior of Lewis bases as agents for promoting chemical reactions is not merely as an electronic complement of the cognate Lewis acids: in fact Lewis bases are capable of enhancing both the electrophilic and nucleophilic character of molecules to which they are bound. This diversity of behavior leads to a remarkable versatility for the catalysis of reactions by Lewis bases.

Lewis Base Catalysis in Organic Synthesis

A highly efficient bifunctional guanidine catalyst was developed for the asymmetric cascade reaction between 2-nitrovinylphenols and azlactones. A wide variety of 3-aminodihydrocoumarin derivatives could be obtained in high yields (up to 99% yield) with excellent enantioselectivities (up to 99% ee) and diastereoselectivities (>19 : 1 dr).

Asymmetric synthesis of 3-aminodihydrocoumarins via the chiral guanidine catalyzed cascade reaction of azlactones

Enantioselective synthesis of 1,2,4-triazolines by chiral iron(II)-complex catalyzed cyclization of α-isocyano esters and azodicarboxylates

Copper/guanidine-catalyzed asymmetric alkynylation of isatin-derived ketimines

An efficient enantioselective Friedel−Crafts alkylation of indoles to ethyl glyoxylate catalyzed by chiral N,N′-dioxide−Sc(III) complex was developed. The corresponding 3-indolyl(hydroxy)acetates compounds were afforded in good yields with high enantioselectivities (up to 95% ee).

Xiaohua Liu

Papers

Asymmetric synthesis of 3-aminodihydrocoumarins via the chiral guanidine catalyzed cascade reaction of azlactones

Enantioselective synthesis of 1,2,4-triazolines by chiral iron(II)-complex catalyzed cyclization of α-isocyano esters and azodicarboxylates

Copper/guanidine-catalyzed asymmetric alkynylation of isatin-derived ketimines

Highly efficient asymmetric synthesis of 3-indolyl(hydroxy)acetates via Friedel-Crafts alkylation of indoles.

Kinetic Resolution of Oxaziridines via Chiral Bifunctional Guanidine-Catalyzed Enantioselective α-Hydroxylation of β-Keto Esters