Atroposelective desymmetrization of 2-arylresorcinols via Tsuji-Trost allylation.

Palladium-catalyzed asymmetric allylic alkylation has proven to be a powerful method for the preparation of a wide variety of chiral molecules. However, the catalytic and atroposelective allylic alkylation is still rare and challenging, especially for biaryl substrates. Herein, we report the palladium-catalyzed desymmetric and atroposelective allylation, in which the palladium complex with a chiral phosphoramidite ligand enables desymmetrization of nucleophilic 2-arylresorcinols in a highly enantioselective manner.

Organocatalytic Atroposelective Synthesis of Isoquinolines via Dynamic Kinetic Resolution.

Herein, a highly enantioselective Pictet-Spengler reaction for the synthesis of axially chiral tetrahydroisoquinolines via dynamic kinetic resolution is described. Chiral phosphoric acids catalyze cyclization to yield single regioisomeric isoquinolines with excellent enantioselectivities around the C-C bond up to 99% ee. The current protocol is effective for a wide range of substrates, and the observed enantiodivergence depends on the substituents on the catalysts.

Janus Graphene Oxide Sheets with FeO Nanoparticles and Polydopamine as Anodes for Lithium-Ion Batteries.

In this study, a one-step process to fabricate "Janus"-structured nanocomposites with iron oxide (FeO) nanoparticles (FeO NPs) and polydopamine (PDA) on each side of a graphene oxide (GO) nanosheet using the Langmuir-Schaefer technique has been proposed. The FeO NPs-GO hybrid is used as a high-capacity active material, while PDA is added as a binder due to its unique wet-resistant adhesive property. The transmission electron microscopy image shows a superlattice-like out-of-plane section of the multilayered nanocomposite, which maximizes the density of the composite materials.

Bottlebrush Copolymer as Surface Neutralizer for Vertical Alignment of Block Copolymer Nanodomains in Thin Films.

Herein we designed bottlebrush copolymers for use as a neutral additive to block copolymer (BCP) thin films in which they are segregated to the interfaces via architectural effects and produce nonpreferential interfaces to induce perpendicular orientation of BCP microdomains. Two BCP systems were employed, a conventional poly(styrene--methyl methacrylate) (PS--PMMA) with relatively low χ and similar surface energies between blocks, and a high χ poly(styrene--methacrylic acid) (PS--PMAA) with distinct surface energies. The bottlebrushes, with either short side-chains of PS--PMMA or PS--PMAA random copolymers, were synthesized via ring-opening metathesis polymerization (ROMP).