Homogeneous carboamination, carboalkoxylation and carbolactonization of terminal alkenes are realized via oxidative gold catalysis, providing expedient access to various substituted N- or O-heterocycles. Deuterium-labeling studies established the anti nature of the alkene functionalization and the indispensible role of Au(I)/Au(III) catalysis. This study constitutes the first example of catalytically converting C(sp(3))-Au bonds into C(sp(3))--C(sp(2)) bonds in a cross-coupling manner and opens new opportunities to study gold alkene catalysis where alkylgold intermediates can be readily functionalized intermolecularly.

It is currently a critical period for the prevention and control of the COVID-19 pandemic. Since the medical waste disposal could be an important way to control the source of infection, standardization, and strict implementation of the management of COVID-19 related medical waste should be with careful consideration to reduce the risk of epidemic within hospitals. This study illustrates the practice of medical waste disposal responding to the 2019-2020 novel coronavirus pandemic.

Oxidizing gold? A gold(I)/gold(III) catalytic cycle is essential for the first oxidative cross-coupling reaction in gold catalysis. By using Selectfluor for gold(I) oxidation, this chemistry reveals the synthetic potential of incorporating gold(I)/gold(III) catalytic cycles into contemporary gold chemistry and promises a new area of gold research by merging powerful gold catalysis and oxidative metal-catalyzed cross-coupling reactions.

An expedient and reliable method for accessing reactive alpha-oxo gold carbenes via gold-catalyzed intermolecular oxidation of terminal alkynes has been developed. Significantly, this method offers a safe and economical alternative to the strategies based on diazo substrates. Its synthetic potential is demonstrated by expedient preparation of dihydrofuran-3-ones containing a broad range of functional groups.

Platinum nanothorn assemblies with sharp tips and edges were prepared, which exhibit high surface enhanced Raman scattering (SERS) activity and yield an enhancement factor as high as 2000 for adsorbed pyridine.

An efficient, formal [4 + 2] synthesis of synthetically valuable piperidin-4-ones from secondary amines in two steps has been achieved via a key gold catalysis without the purification of tertiary amine intermediates. This reaction is selective toward the less-substituted alkyl group and shows moderate to excellent diastereoselectivities. Its synthetic potential in alkaloid synthesis is demonstrated in a highly diastereoselective synthesis of (+/-)-cermizine C.

A novel Au-catalyzed homogeneous oxidative C-O bond-forming reaction involving a Au(I)/Au(III) catalytic cycle is developed. Mechanistic studies reveal the involvement of a unique intramolecular carboxy migration. From readily available propargylic benzoates, this chemistry allows efficient access to captodative alkenes and dienones, demonstrating the synthetic potential of incorporating Au(I)/Au(III) catalytic cycles into contemporary Au chemistry. The unique reactivity and the mechanistic insights would help open a new research area in gold catalysis.

In an attempt to understand the single-molecule SERS of some small nonresonant molecules, such as adenine, it is inevitable to include the chemical enhancement mechanism to provide additional enhancement to the electromagnetic mechanism, although it may be much smaller than the electromagnetic field enhancement. We will report here the first experimental investigation of the charge-transfer (CT) enhancement of protonated adenine molecules on Rh and Pd by performing the potential-dependent SERS using one UV laser (325 nm) and two visible lasers (514.5 and 632.8 nm). A UV laser displays a significant role in the verification of the CT process due to its much larger photon energy and thus a much larger shift of potential of the maximum SERS intensity (E-max) than visible lasers. We find a well-discernible E-max and a linear relationship between E-max and the photon energy of the laser for adenine on both Rh and Pd surfaces. The E-max was found to shift positively with the increasing photon energy, which strongly indicates an electron transfer from the E-f of Rh and Pd to the lowest unoccupied orbital of adenine molecules. In addition, different contributions of CT enhancement to adenine Raman bands are also briefly discussed. By analyzing the wavelength-dependent intensity change and UV-vis absorption spectroscopy, we propose the contribution of preresonance Raman enhancement to the UV-SERS signal for the band at around 1330 cm(-1). The present study demonstrates that the use of a UV laser opens a promising way to understand the enhancement mechanism, especially the chemical enhancement mechanism.Natural Science Foundation of China [20825313, 20827003, 20973143, 20903076]; MOST of China [2009CB930703