Chao Wang 교수

A highly enantioselective three-component cascade reaction, consisting of an enantioselective [4+2] cycloaddition reaction catalyzed by chiral phosphoric acid and a subsequent catalytic intramolecular hydroamination by gold(I) complex, provides a unique method to access structurally diverse julolidine derivatives in high optical purity.

Silicon-containing compounds are widely used as synthetic building blocks, functional materials, and bioactive reagents. In particular, silyl radicals are important intermediates for the synthesis and transformation of organosilicon compounds. Herein, we describe the first protocol for the generation of silyl radicals by photoinduced decarboxylation of silacarboxylic acids, which can be easily prepared in high yield on a gram scale and are very stable to air and moisture. Irradiation of silacarb

An etheric Negishi coupling: The first cross-coupling reaction between aryl alkyl ethers and dianion-type zincate reagents to afford biaryl compounds through selective cleavage of the etheric C(sp(2))-O bond was developed. Dianion-type zincates showed excellent reactivity toward the aromatic ethers under mild conditions, with good functional group compatibility (see scheme).

Contrary to all previous reports, bromoboration of propyne with BBr(3) proceeds in >or=98% syn-selectivity to produce (Z)-2-bromo-1-propenyldibromoborane (1). Although 1 is readily prone to stereoisomerization, it can be converted to the pinacolboronate (2) of >or=98% isomeric purity by treatment with pinacol, which may then be subjected to Negishi coupling to give trisubstituted (Z)-alkenylpinacolboronates (3) containing various R groups in 73-90% yields. Iodinolysis of 3 affords alkenyl iodide

In this paper, the anisotropic thermal conductivity characteristics of graphene wrinkles are observed for the first time using a non-equilibrium molecular dynamics method. Our results reveal that the wrinkling level has little effect on the thermal conductivity along the wrinkling direction. However, the wrinkling level plays an important role in the reduction of thermal conductivity along the texture direction, which results from the contributions of increased bond length, von Mises stress, bro

Ni-catalyzed cross-coupling between aryl alkyl ethers (ArOR) and Grignard reagents (RMgBr), known since 1979, proceeds under mild conditions in many cases. Although the reaction routes of various synthetic protocols involving transition-metal-catalyzed C-O bond activation have been elucidated, the mechanism of this etheric Kumada-Tamao-Curriu reaction remains enigmatic. This is because oxidative addition of inert etheric C-O to Ni(0) is thermodynamically and kinetically unfavorable, making it ha

Isoindoline derivatives with high enantiomeric purity (up to 98% ee) have been accessed by formal double arylation of azomethines.

Herein we report a versatile Mizoroki-Heck-type photoinduced C(sp³ )-N bond cleavage reaction. Under visible-light irradiation (455 nm, blue LEDs) at room temperature, alkyl Katritzky salts react smoothly with alkenes in a 1:1 molar ratio in the presence of 1.0 mol % of commercially available photoredox catalyst without the need for any base, affording the corresponding alkyl-substituted alkenes in good yields with broad functional-group compatibility. Notably, the E/Z-selectivity of

We have developed a simple and direct method for the synthesis of aryl ethers by reacting alcohols/phenols (ROH) with aryl ammonium salts (ArNMe₃⁺ ), which are readily prepared from anilines (ArNR'₂ , R'=H or Me). This reaction proceeds smoothly and rapidly (within a few hours) at room temperature in the presence of a commercially available base, such as KO^t Bu or KHMDS, and has a broad substrate scope with respect to both ROH and ArNR'₂ . I

The first metal-mediated efficient synthesis of octasubstituted semibullvalenes, including octaalkyl and mixed tetraalkyl and tetraphenyl derivatives, was developed. The structures of these semibullvalenes were determined by single-crystal X-ray structural analysis. Their intramolecular skeletal rearrangement and reaction chemistry were investigated.

Various aryl-, alkenyl-, and/or alkyllithium species reacted smoothly with aryl and/or benzyl ethers with cleavage of the inert C-O bond to afford cross-coupled products, catalyzed by commercially available [Ni(cod)₂ ] (cod=1,5-cyclooctadiene) catalysts with N-heterocyclic carbene (NHC) ligands. Furthermore, the coupling reaction between the aryllithium compounds and aryl ammonium salts proceeded under mild conditions with C-N bond cleavage in the presence of a [Pd(PPh₃ )<s

Lithio siloles of diversified structures and substitution patterns were highly efficiently formed from readily available silyl 1,4-dilithio-1,3-butadienes via novel intramolecular skeletal rearrangements.

Substituted cyclooctatetraenes are a class of interesting and important compounds both theoretically and synthetically. Since Reppe first discovered the Ni-catalyzed tetramerization of ethyne affording cyclooctatetraene in 1948, transition metal mediated synthesis of this type of compounds has become a primary methodology. In this Feature Article, based on our own recent results and other groups' related reports, we describe major achievements on transition metal mediated or catalyzed synthetic

Programming the organization of semiconducting polymers to form well-defined nanoarchitectures is desirable for fabricating functional materials. In this work, semiconducting copolymers, poly(cholesterol allene)-b-poly(3-hexylthiophene) (PCA-b-P3HT) containing helical PCA and poly(alkoxy allene)-b-poly(3-hexylthiophene) (PAA-b-P3HT) containing achiral PAA segments, were prepared. Crystallization of P3HT and helicity of PCA drove PCA-b-P3HT self-assemble into spherical nanoparticles that graduall