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In graphene electronics applications, in order to obtain the size and pattern required for the device, it is often necessary to photolithography the graphene after growth, resulting in contamination of graphene by the photoresist which have doping effect. Therefore, in order to avoid this effect, this article focused on directly grown patterned graphene. Based on atmospheric pressure chemical vapour deposition (APCVD) technology, patterned graphene was successfully grown on SiO2/Si by metal proximity catalytic effect. The patterned graphene was characterized by Raman spectroscopy and optical microscope. The effects of parameters such as gas flow, growth temperature, and growth time on the growth of patterned graphene were explored, and the best results were obtained. Metal copper and cobalt thin films were used for assisted catalysis, respectively, and the mechanism of metal proximity catalysis was explored. The experimental results showed that proximity catalysis is a catalytic growth mechanism based on surface diffusion. The growth method avoids using photolithography to make patterns, and can grow patterned graphene on insulating substrates or semiconductors in one step, which is of great significance for making patterned graphene and applying them to semiconductor devices. [ABSTRACT FROM AUTHOR]

Multicomponent Synthesis of 5-Cyano-pyrazolo[1,5-a]pyrimidines Enabled by Aerobic Manganese Catalysis Keywords: Manganese catalysis; Strecker reaction; Multicomponent reaction; Cyanation EN Manganese catalysis Strecker reaction Multicomponent reaction Cyanation 871 876 6 03/27/23 20230321 NES 230321 An aerobic Mn(III)-catalyzed one-pot three-component synthesis of 5-cyano-pyrazolo[1,5- I a i ]pyrimidines has been described. These results revealed that the tandem reaction starts with the Strecker reaction and Mn(OAc) SB 3 sb - 2H SB 2 sb O is essential in the following oxidative cyclization process. All of these control experiments strongly support that this tandem reaction involves the Strecker reaction and the sequential Mn-catalyzed cyclization to afford the desired product B 4 aa b . [Extracted from the article]

• Dual zerovalent nonmetal doped Ni2P nanoparticles/N,B-graphene hybrid catalysts (N,B-Ni2P/G) are reasonably designed and synthetized. • N,B-Ni2P/G showed improved hydrogen evolution activity at all pH values. • The enhanced activity was ascribed to the optimized water and hydrogen adsorption free energy by N,B atoms dual incorporation. The large-scale implementation of hydrogen by electrochemical water splitting demands highly active, durable and inexpensive platinum-free catalysts. Nevertheless, developing efficient non-noble metal based hydrogen evolution reaction (HER) electrocatalysts that can work in all pH solutions still remains as a huge uphill. Herein, we report dual zerovalent nonmetal (N and B) doped Ni 2 P nanoparticles hybridized with N, B-graphene (N, B-Ni 2 P/G) could function as electrocatalyst for hydrogen evolution in all pHs with high activity and stability. In-situ phosphidation of a 2D/2D heterojunction of Ni-B i nanosheets/graphene (Ni-B i NS/G) under ammonia atmosphere results in a strongly couple N, B-Ni 2 P/G hybrid electrocatalyst with (i) the enhanced intrinsic catalytic activity from dual zerovalent doped Ni 2 P structure, (ii) 0D architectures with a high surface area exposure yield, and (iii) the enhanced charge transport ability by N, B-graphene support. As a result, the designed N, B-Ni 2 P/G exhibits superior electrocatalytic HER performance and remarkable stability at all pH ranges. Our protocol may open up new ways to design progressive electrocatalysts for energy-related applications. [ABSTRACT FROM AUTHOR]

The front cover picture, provided by Sen Liang, Kun Xu, Cheng‐Chu Zeng, Hong‐Yu Tian, Bao‐Guo Sun, exhibits the advances in using electrochemistry for α‐C−H oxidative functionalization of carbonyl compounds. α‐C−H bond functionalization of carbonyl compounds to afford more versatile functionalized groups has become a promising strategy for atom‐economical C−C and C−X bond formation. Organic electrosynthesis is revolutionizing the way of organic synthesis, and this field has seen explosive growth in recent years. Details can be found in the review on pages 4266–4292 (S. Liang, K. Xu, C.‐C. Zeng, H.‐Y. Tian, B.‐G. Sun, Adv. Synth. Catal. 2018, 360, 4266–4292; DOI: 10.1002/adsc.201800519). [ABSTRACT FROM AUTHOR]

The scalable method represents the first coupling of aryl tetrazoles with mono and 1,1-disubstituted allenes. [ABSTRACT FROM AUTHOR]

An abstract of the article "Regio- and Enantioselective Synthesis of N-Substituted Pyrazoles by Rhodium-Catalyzed Asymmetric Addition to Allenes" by A. M. Haydl and colleagues is presented.

The scalable transformation is based on a benzoic acid/rhodium-catalyst system which affords branched allylic sulfones with good to excellent yields and selectivities. [ABSTRACT FROM AUTHOR]

A library of easily tunable, sterically bulky ligands is synthesized among which the one shown causes the highest conversions and enantiomeric excesses for the products as well as the best ratio of branched to linear products. [ABSTRACT FROM AUTHOR]

In course of this study the reaction is also conducted in water for the first time. [ABSTRACT FROM AUTHOR]

• Trace sulfone helps NH 4 I dissolve in ether-based electrolytes for Li-S batteries. • Sulfone-assisted-NH 4 I additive shows synergistic dissolution and catalysis effects. • Sulfone-assisted-NH 4 I additive reduces the voltage barrier of Li 2 S cathode. • Sulfone-assisted-NH 4 I additive enhances electrochemical performances of Li 2 S. Li 2 S is highly desired for high energy-density lithium sulfur batteries since it allows to be matched with Li metal-free anodes and alleviates the volume expansion of S cathode. However, Li+ extraction from Li 2 S usually suffers from a huge voltage barrier due to its poor electron conductivity and sluggish Li+ ion diffusion during activation. In this work, trace sulfone-assisted-NH 4 I is adopted as an electrolyte additive with synergistic dissolution and catalysis effects to alleviate the voltage barrier of Li 2 S. On one hand, the intercalation between sulfone-NH 4 + and Li 2 S turns solid Li 2 S into liquid phase, which significantly speeding up the transport of electrons and Li+ ions during activation. On the other hand, I− works as a redox mediator, which further facilitates the oxidation of Li 2 S to polysulfides. By taking the advantages of synergistic dissolution and catalysis effects from sulfone-NH 4 + and I−, the Li 2 S cathode can be activated at ~3.0 V with a very flat plateau. Finally, the Li 2 S cathode cycled in the electrolyte with optimized 0.5% sulfone-assisted-NH 4 I additive shows a high initial discharge capacity of 1160 mAh g−1 at 0.05C, along with enhanced cycling performances and rate capabilities. [ABSTRACT FROM AUTHOR]

The scalable title reaction tolerates variously functionalized 2H-[1,2′-bipyridin]-2-ones as well as aryl and hetaryl substituted propargyl alcohols, but no alkyl substituted derivatives of the latter. [ABSTRACT FROM AUTHOR]

Anthranilic acid amides are cyclized to the corresponding dihydro-quinazolinones in good yields with dicumyl peroxide as radical methyl donor. [ABSTRACT FROM AUTHOR]

N-Methyl pyrrole, furan and thiophene do not react with (Ia). [ABSTRACT FROM AUTHOR]

2-Aryloylpyridines or quinolines efficiently react with aryl or alkyl substituted α-amino acids, thus offering not only a novel approach to 1,3-diaryl substituted imidazo[1,5-a]pyridines, but also to 3-alkyl-1-aryl substituted derivatives which are difficult to access by previously developed methods. [ABSTRACT FROM AUTHOR]

An efficient Cu(II)-catalyzed oxidative amination of sp3 C-H bonds using air as the terminal oxidant is presented. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Cerium(III)-Catalyzed Cascade Cyclization: An Efficient Approach to Functionalized Pyrrolo[1,2-a]quinolines" by C. Feng and others, published in the periodical "Organic & Biomolecular Chemistry" in 2014.