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Disclosed herein is RhCl3-catalyzed peri-selective C-H/C-H oxidative homo-coupling of 1-substituted naphthalenes, which provides a highly efficient and streamlined approach to chalcogen-embedded anthanthrenes from readily available starting materials. Introducing O, S, and Se into the anthanthrene skeleton leads to gradually increased π-π stacking distances but significantly enhanced π-π overlaps with the growth of heteroatomic radius. Moderate π-π distance, overlap area, and intermolecular S-S interactions endow S-embedded anthanthrene (PTT) with excellent 2D charge-transport properties. Moreover, the transformation of p-type to n-type S-embedded anthanthrenes is realized for the first time via the S-atom oxidation from PTT to PTT-O4. In organic field-effect transistor devices, PTT derivatives exhibit hole transport properties with mobilities up to 1.1 cm2 V-1 s-1, while PTT-O4 shows an electron transport property with a mobility of 0.022 cm2 V-1 s-1.

All-inorganic cesium lead halide perovskites have received much attention, but the study of the formation pathway is relatively little. We report here a new one-step approach for the synthesis of C...

A concise synthesis of phenanthridine derivatives is achieved by an iridium-catalyzed direct fusion of oxime ethers and heteroarenes, which is a successful example of a cascade C–H/C–H cross-coupli...

Four types of colloidal semiconductor CdTe magic-size clusters (MSCs), each of which is in a single-ensemble form, have been obtained at room temperature from a single induction period (IP) sample in dispersion. The induction period is the prenucleation stage that occurs prior to nucleation and growth of colloidal quantum dots (QDs). Three types display sharp optical absorption peaking at either 371, 417, or 448 nm, and the fourth type exhibits a sharp absorption doublet with peaks at 350 and 371 nm. These MSCs are respectively denoted as sMSC-371, sMSC-417, sMSC-448, and dMSC-371. We show that the evolution of the various MSCs is affected by the nature of their dispersions. We hypothesize that the evolution of MSCs involves their precursor compounds (PCs), which are transparent in optical absorption. The present study explores new avenues for the exclusive synthesis of four types of CdTe MSCs (with each in a single-ensemble form) and provides an improved understanding for their formation.

An unprecedented Rh-catalyzed ketone-directed vinylic C-H activation/[4+2] O-annulation of α-aryl enones with internal alkynes followed by a Cu-catalyzed ring contraction in air to provide multiaryl-substituted furan derivatives has been developed. The preliminary mechanism study identifies the active pyrylium salt as the key intermediate.

A cascade double C–H annulation of aldoximes with alkynes to produce benz[a]acridizinium salts is developed by using a simple catalytic system of [Cp*Rh(OAc)2]2 in the presence of Zn(OTf)2 with oxygen as the sole oxidant. In addition, the challenging C–H annulation of aldoximes with alkynes, especially arylalkynes, to synthesize 1H-isoquinolines is also achieved under slightly modified conditions. This protocol provides an efficient one-pot access to multisubstituted dehydroberberinium skeletons from simple starting materials, which can be easily transformed into berberinium and tetrahydroberberine skeletons by controlled hydrogenation.

A transition-metal-free and room-temperature coupling/decarboxylation reaction between α-oxocarboxylates and α-bromoketones is reported herein. It represents the first mild and regioselective synthesis of either 1,2- or 1,3-diketones from the same starting materials. Notably, the regioselectivity is simply controlled by solvents. The preliminary experimental data and DFT calculations suggest sequential Darzens-type coupling, alkaline hydrolysis, KOH-promoted oxirane opening and decarboxylation in one pot. This method is efficient for the synthesis of α,β-epoxy-γ-butyrolactone and curcuminoids.

We report, for the first time, the synthesis of CdS magic-size clusters (MSCs) which exhibit a single sharp absorption peaking at ∼ 361 nm, along with sharp band edge photoemission at ∼ 377 nm and broad trap emission peaking at ∼ 490 nm. These MSCs are produced in a single-ensemble form without the contamination of conventional quantum dots (QDs) and/or other-bandgap clusters. They are denoted as MSC-361. We present the details of several controlled syntheses done in oleylamine (OLA), using Cd(NO3)2 or Cd(OAc)2 as a Cd source and thioacetamide (TAA) or elementary sulfur (S) as a S source. A high synthetic reproducibility of the reaction of Cd(NO3)2 and TAA to single-ensemble MSC-361 is achieved, the product of which is not contaminated by other bandgap clusters and/or QDs. In some cases, the reaction product exhibits an additional absorption peak at ∼ 322 nm. We demonstrate that the two peaks, at 361 and 322 nm, do not evolve synchronously. Therefore, the 322 nm peak is not a higher order electronic transition of MSC-361, but due to the presence of another ensemble, namely MSC-322. The present study suggests that there is an outstanding need for the development of a physical model to narrow the knowledge gap regarding the electronic structure in these colloidal semiconductor CdS MSCs.

An air-stable half-sandwich ruthenium(II) complex, [Ru(p-cymene)(MeCN)3](SbF6)2, was synthesized and characterized. It exhibited unique catalytic ability in a [3+2] annulation reaction of 2-arylcyclo-2-enones with internal alkynes via C(sp(2))-H/alkene functionalization, which offered a rapid and atom-economical methodology to construct various synthetically challenging spiro carbocyclic indenes bearing a quaternary carbon.

Herein the Cu-catalyzed direct C–H mono-, di- and triarylations of imidazolium salts with aryl iodides/bromides are accomplished for the first time. The unprecedented alkenylation and alkynylation are also realized using alkenyl and alkynyl iodides, respectively. Moreover, triarylated imidazolium salts with different substituents can be accessed in a modular and one-pot manner. This protocol provides an efficient tool for the assembly of diverse imidazolium-based ionic functional materials. As applicable examples, an electrochromic bisbenzimidazolium salt 7 and a photochromic triarylimidazolium salt 8 are easily obtained.

A cascade double C-H annulation of aldoximes with alkynes to produce benz[a]acridizinium salts is developed by using a simple catalytic system of [Cp*Rh(OAc)