Palladium-Catalyzed Direct Esterification via C-H Bond Activation of Aldehydes.

A concise and highly efficient synthesis method of direct esterification of aldehydes via Pd-catalyzed C-H bond activation of aldehyde group has been developed. The strategy avoids the preoxidation step of aldehyde or use of condensing agents in ester synthesis, which is not only applicable to various alcohols but also suitable for the esterification of phenolics which are usually difficult to be esterified. The methodology has the significant advantages of broad substrate scope, mild reaction conditions, and nonrequirement of additional oxidants.

Palladium-catalyzed and alcohol-enabled transformation to synthesize benzocyclic ketones.

Catalytic carbonyl formation ranks as one of the most important synthetic methodologies. Herein, a highly effective palladium-catalyzed and alcohol-promoted transformation of nitriles to synthesize benzocyclic ketones is described. It provides a straightforward access to potentially valuable indanone compounds in high yields in the presence of alcohol.

New lead-free perovskite RbBiCl nanocrystals with blue luminescence and excellent moisture-stability.

The development of nontoxic and stable all-inorganic perovskite nanocrystals (NCs) represents a major challenge to unlock widely practical applications in photoelectric fields. It is an effective strategy to discover nontoxic metal perovskite nanocrystals (NCs) with excellent optical properties. In addition, it has been proved that alkali metals such as rubidium (Rb) and potassium (K) have a good influence on improving the optical performance of perovskites.

Syntheses, crystal structures and optical properties of two one-dimensional germanophosphates: HRbGe(HPO) and CsGe(HPO)(OH).

Germanophosphates, as a young class of metal phosphates, have been less reported but might possess more diverse structural types and potential applications. Here, two one-dimensional (1D) alkali-metal germanophosphates (GePOs), namely, hydrogen hexakis(μ-hydrogen phosphato)digermaniumtrirubidium, HRbGe(HPO) (1), and caesium bis(μ-hydrogen phosphato)(μ-hydroxido)germanium, CsGe(HPO)(OH) (2), have been prepared by the solvothermal method. Compound 1 shows 1D [Ge(HPO)] chains along the c axis formed by GeO octahedra and PO tetrahedra, with Rb cations dissociated between the chains.

Tuning optical properties of perovskite nanocrystals by supermolecular mercapto-β-cyclodextrin.

This study reports a host-guest interaction strategy for systematically manipulating the optical properties of cesium lead halide perovskite nanocrystals (CsPbBr NCs) by protectant-mediated mercapto-β-cyclodextrin (SH-β-CD). The fluorescence of CsPbBr NCs can be adjusted over 405-510 nm with the quantum yields (QY) maintained at 50-90%.

[Highlights on the design procedure of corneal refractive surgery].

Corneal refractive surgery, especially excimer laser corneal refractive surgery, has been used nearly 20 years in China. As the development of high technology and the change of life style, people who received refractive surgery not only demands good visual acuity but also good visual quality. In recent years, more and more new techniques and equipments have sprung up in this field.