Iridium-Catalyzed Ortho-Selective C-H Borylation of Aryl Ketones with Transient Imine Ligands.

Ortho-selective C-H borylation of aromatic ketones has not been extensively explored. Herein, we report the iridium-catalyzed ortho-selective C-H borylation of aromatic ketones using in situ-formed imine as the ligand. Good compatibility is observed for various substituted acetophenones and other aromatic ketones, and corresponding products are obtained with medium to excellent yields.

Recent progress on underwater soft robots: adhesion, grabbing, actuating, and sensing.

The research on biomimetic robots, especially soft robots with flexible materials as the main structure, is constantly being explored. It integrates multi-disciplinary content, such as bionics, material science, mechatronics engineering, and control theory, and belongs to the cross-disciplinary field related to mechanical bionics and biological manufacturing. With the continuous development of various related disciplines, this area has become a hot research field. Particularly with the development of practical technologies such as 3D printing technology, shape memory alloy, piezoelectric materials, and hydrogels at the present stage, the functions and forms of soft robots are constantly being further developed, and a variety of new soft robots keep emerging. Soft robots, combined with their own materials or structural characteristics of large deformation, have almost unlimited degrees of freedom (DoF) compared with rigid robots, which also provide a more reliable structural basis for soft robots to adapt to the natural environment. Therefore, soft robots will have extremely strong adaptability in some special conditions. As a type of robot made of flexible materials, the changeable pose structure of soft robots is especially suitable for the large application environment of the ocean. Soft robots working underwater can better mimic the movement characteristics of marine life in the hope of achieving more complex underwater tasks. The main focus of this paper is to classify different types of underwater organisms according to their common motion modes, focusing on the achievements of some bionic mechanisms in different functional fields that have imitated various motion modes underwater in recent years (e.g., the underwater sucking glove, the underwater Gripper, and the self-powered soft robot). The development of various task types (e.g., grasping, adhesive, driving or swimming, and sensing functions) and mechanism realization forms of the underwater soft robot are described based on this article.

Design of improved four-coil structure with high uniformity and effective coverage rate.

Helmholtz coils have extensive applications in biological medicine, aerospace, and other industries depending on the simple structure and miraculous magnetic field characteristics. However, the uniform zone generated by them is not appropriate for scientific experiments with large devices. Due to the limitations of Helmholtz coils in application, a novel design technique is proposed to improve the homogeneity and region of magnetic field. The main approach is to add an auxiliary coil on each side of Helmholtz coils to compensate for the magnetic field that exists farther out from the center point. To analyze the size relationship between the auxiliary coil and the main coil to obtain the best magnetic field distribution, the traditional Maclaurin expansion method and particle swarm optimization (PSO) algorithm are used to research and discuss. The magnetic field distribution and the corresponding effective coverage rate (ECR) of the improved schemes with different structural parameters are calculated under the relative deviations of 0.1%, 0.5% and 1%, respectively. The results obtained by the above optimization methods are verified by the finite element software COMSOL and specific experiments. Both optimization methods manifest that the maximum effective coverage rate can be achieved when the size of the auxiliary coil is consistent with that of the main coil. In addition, we compare the improved four-coil structure proposed in this paper with the existing four-coil square structure under the same volume. The data show that the improved structure has certain advantages in the spatial magnetic field distribution. The corresponding tri-axial coil system is established by adopting the parameters on the single axis, which can achieve a constant magnetic field in arbitrary directions by controlling the magnitude and direction of current on each axis. This provides a theoretical basis for the application of magnetic navigation technology.

Dual Nickel/Ruthenium Strategy for Photoinduced Decarboxylative Cross-Coupling of α,ß-Unsaturated Carboxylic Acids with Cycloketone Oxime Esters.

Herein, a dual nickel/ruthenium strategy is developed for photoinduced decarboxylative cross-coupling between α,ß-unsaturated carboxylic acids and cycloketone oxime esters. The reaction mechanism is distinct from previous photoinduced decarboxylation of α,ß-unsaturated carboxylic acids. This reaction might proceed through a nickelacyclopropane intermediate. The C(sp2)-C(sp3) bond constructed by the aforementioned reaction provides an efficient approach to obtaining various cyanoalkyl alkenes, which are synthetically valuable organic skeletons in organic and medicinal chemistry, under mild reaction conditions. The protocol tolerates many critical functional groups and provides a route for the modification of complex organic molecules.

Synthesis of trisubstituted alkenes by Ni-catalyzed hydroalkylation of internal alkynes with cycloketone oxime esters.

A method for Ni-catalyzed hydroalkylation of internal alkynes with cycloketone oxime esters was developed. The reaction has a broad substrate scope. This hydroalkylation shows excellent regio- and stereo-selectivity. This method enables readily available starting materials to be used to access a range of cyano-substituted single-configuration trisubstituted alkenes. These are valuable feedstock chemicals and are widely used in synthetic and medicinal chemistry.

Synthesis of gem-difluoroalkenes via nickel-catalyzed allylic defluorinative reductive cross-coupling of trifluoromethyl alkenes with epoxides.

A nickel-catalyzed defluorinative reductive cross-coupling of trifluoromethyl alkenes with epoxides has been developed. Various substituted trifluoromethyl alkenes and epoxides were found to be suitable reaction substrates. This reaction enabled C(sp3)-C(sp3) bond construction through allylic defluorinative cross-coupling of trifluoromethyl alkenes under mild reaction conditions. This methodology was highly compatible with various sensitive functional groups, providing access to a diverse array of functionalized gem-difluoroalkene-containing alcohol compounds.

UVC-assisted electrochemical degradation of novel bisphenol analogues with boron-doped diamond electrodes: kinetics, pathways and eco-toxicity removal.

In the present study, the UVC-assisted electrochemical degradation ofthree novel bisphenol analogues (BPs; including bisphenol F, S, and B, i.e., BPF, BPS and BPB, respectively), along with bisphenol A (BPA), was investigated using boron-doped diamond (BDD) electrode. At first, this study demonstrated a significant influence ofcurrent density on the degradation rates of BPF by the BDD anode. The pseudo-first order rate constants for BPF were calculated as 0.012, 0.028 and 0.029 min-1 at the applied current densities of 10, 20 and 30 mA/cm2, respectively. UVC irradiation significantly enhanced the electrochemical degradation of BPF in the concentration range from 5 to 30 mg/L, with synergistic effects in the range of 32.0%-40.9%. The UVC-BDD electrolysisshowed comparable or even lower electric energy per order (EEO) than single BDD electrolysis. The UVC-assisted degradation of the investigated BPs showed decreased pseudo-first order rate constants in the following order: BPF > BPA > BPB > BPS. Based on the identifiedtransformation products, UVC-assisted electrochemical degradation pathways of the novel BPs were proposed to be mainly hydroxylation and bond-cleavage. UVC irradiation has been proved to promote the formation of hydroxyl radicals by BDD electrode to facilitate the degradation process. For these BPs, nearly 100% mineralization can be achieved by a modified strategy using a short-time UVC-assisted BDD electrolysis (120 min) that is followed by UVC photolysis (360 min). Finally, the eco-toxicity of the BPs solutions towardsVibrio Fischeri was significantly removed after 120 min of the electrochemical degradation period. Based on these results, the UVC-assisted electrochemical treatment using a BDD electrode can be considered a promising technology for the removal of novel BPs and the reduction of their hazardous effects to aqueous environments.

Base-free Ni-catalyzed Suzuki-type cross-coupling reactions of epoxides with boronic acids.

A Ni-catalyzed Suzuki-type cross-coupling of boronic acids with epoxides without an exogenous base and with broad substrate scope has been developed. The product selectivity of styrenyl epoxides is different from that of previous work. This methodology uses readily available starting materials to access a range of substituted alcohols, which are valuable feedstock chemicals.

Enhanced degradation of triphenyl phosphate (TPHP) in bioelectrochemical systems: Kinetics, pathway and degradation mechanisms.

Triphenyl phosphate (TPHP) is one of the major organophosphate esters (OPEs) with increasing consumption. Considering its largely distribution and high toxicity in aquatic environment, it is important to explore an efficient treatment for TPHP. This study aimed to investigate the accelerated degradation of TPHP in a three-electrode single chamber bioelectrochemical system (BES). Significant increase of degradation efficiency of TPHP in the BES was observed compared with open circuit and abiotic controls. The one-order degradation rates of TPHP (1.5 mg L-1) were increased with elevating sodium acetate concentrations and showed the highest value (0.054 ±â€¯0.010 h-1) in 1.0 g L-1 of sodium acetate. This result indicated bacterial metabolism of TPHP was enhanced by the application of micro-electrical field and addition acetate as co-substrates. TPHP could be degraded into diphenyl phosphate (DPHP), hydroxyl triphenyl phosphate (OH-TPHP) and three byproducts. DPHP was the most accumulated degradation product in BES, which accounted more than 35.5% of the initial TPHP. The composition of bacterial community in BES electrode was affected by the acclimation by TPHP, with the most dominant bacteria of Azospirillum, Petrimonas, Pseudomonas and Geobacter at the genera level. Moreover, it was found that the acute toxic effect of TPHP to Vibrio fischeri was largely removed after the treatment, which revealed that BES is a promising technology to remove TPHP threaten in aquatic environment.