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The title compound, a key intermediate for preparing coenzyme Q analogues, was prepared in excellent yield by a reaction sequence starting from the commercially available 3,4,5-trimethoxybenzadehyde via Wolff–Kishner reduction, selective bromination, methoxylation and Blanc chloromethylation reaction.

Given that bromine possesses similar properties but extra merits of easily synthesizing and polarizing comparing to homomorphic fluorine and chlorine, it is quite surprising very rare high-performance brominated small molecule acceptors have been reported. This may be caused by undesirable film morphologies stemming from relatively larger steric hindrance and excessive crystallinity of bromides. To maximize the advantages of bromides while circumventing weaknesses, three acceptors (CH20, CH21 and CH22) are constructed with stepwise brominating on central units rather than conventional end groups, thus enhancing intermolecular packing, crystallinity and dielectric constant of them without damaging the favorable intermolecular packing through end groups. Consequently, PM6:CH22-based binary organic solar cells render the highest efficiency of 19.06% for brominated acceptors, more excitingly, a record-breaking efficiency of 15.70% when further thickening active layers to ~500 nm. By exhibiting such a rare high-performance brominated acceptor, our work highlights the great potential for achieving record-breaking organic solar cells through delicately brominating. The relatively larger steric hindrance and excessive crystallinity of bromides could lead to undesirable film morphologies. Here, the authors take advantage of bromides and construct small molecule acceptors with stepwise bromination and realize maximum efficiency of 19% in organic solar cells.

Cis -[Mo VI O 2 (CH 3 -hptb)(MeOH)] ( 1 ) has been synthesized by the reaction of [Mo VI O 2 (acac) 2 ] and deferasirox [ICL670: 4-[3,5-bis(2-hydroxyphenyl)-1H-1,2,4-triazol-1-yl]benzoic acid, H 3 hptb, I ] in 1:1 molar ratio in MeOH. Complex 1 has been characterized successfully by several spectral techniques, viz. FT-IR, UV–Vis, 1 H and 13 C NMR, elemental (CHN) and thermogravimetric analysis. The esterification of the carboxylic group of ligand was observed during the complexation process with molybdenum. The analogous heterogeneous complex [Mo VI O 2 (hptb)(MeOH)]@APTMS-TiO 2 ( 2 ) has been synthesized by immobilizing I on amine-functionalized TiO 2 , {[H 2 hptb]@APTMS-TiO 2 ( II )} and then reacting it with [Mo VI O 2 (acac) 2 ] in MeOH. Characterization of the immobilized complex was achieved through FT-IR, DRS, P-XRD, TEM, thermogravimetric analysis and MP-AES. Both the complexes have been utilized in synthesizing organobromine compounds through oxidative bromination of styrene in the presence of KBr, oxidant (30% aq. H 2 O 2 ) and 70% aq. HClO 4 at room temperature. With the formation of 2-bromo-1-phenylethane-1-ol and 1-phenylethane-1,2-diol under the optimized reaction conditions, 72 and 100% conversion of styrene was achieved in the presence of catalysts 1 and 2 , respectively. The oxidative bromination of thymol with catalyst 2 provides 2-bromothymol (52%) and 2,4-dibromothymol (48%) with 100% conversion. Graphical Abstract Dioxidomolybdenum(VI) complex of ICL670 immobilized on amine-functionalized titania has been synthesized and used as a functional model of haloperoxidases for the oxidative bromination of thymol and styrene.

The commercially available 7-methoxy-?-tetralone was subjected to bromination, reduction and protection respectively to obtain the tert-butyldimethylsilyl derivative compound whose conversion into the title compound tetralone was accomplished in three steps (methylation, deprotection and oxidation).

Regioselective benzanilide bromination that generates either regioisomer from the same starting material is desirable. Herein, we develop switchable site-selective C(sp2)-H bromination by promoter regulation. This protocol leads to regiodivergent brominated benzanilide starting from the single substrate via selection of promoters. The protocol demonstrates excellent regioselectivity and good tolerance of functional groups with high yields. The utility effectiveness of this method has been well exemplified in the late-stage modification of biologically important molecules.

The monolithic integration of new optoelectronic materials with well-established inexpensive silicon circuitry is leading to new applications, functionality and simple readouts. Here, we show that single crystals of hybrid perovskites can be integrated onto virtually any substrates, including silicon wafers, through facile, low-temperature, solution-processed molecular bonding. The brominated (3-aminopropyl)triethoxysilane molecule binds the native oxide of silicon and participates in the perovskite crystal with its ammonium bromide group, yielding a solid mechanical and electrical connection. The dipole of the bonding molecule reduces device noise while retaining signal intensity. The reduction of dark current enables the detectors to be operated at increased bias, resulting in a sensitivity of 2.1 × 10 4  µC Gy air −1  cm −2 under 8 keV X-ray radiation, which is over a thousand times higher than the sensitivity of amorphous selenium detectors. X-ray imaging with both perovskite pixel detectors and linear array detectors reduces the total dose by 15–120-fold compared with state-of-the-art X-ray imaging systems. Hybrid perovskite crystals are integrated onto silicon wafers enabling fabrication of an X-ray linear detector array. High sensitivity may reduce patient dose in medical imaging applications.

A wide range of brominating agents and heterogeneous brominating systems indicates a demand in the field of organic compounds bromination. A new mild and recyclable metal‐organic framework (MOF)‐based brominating agent, Br2@CAU‐10‐PDC (CAU = Christian‐Albrechts‐University), has been synthesized and successfully applied to the bromination of activated aromatics, such as phenols, amines, and amides. Infrared and Raman spectroscopy as well as powder X‐ray diffraction are used to characterize the obtained composite. Rietveld refinement of the composite structure has also been performed; as a result, the positions of bromine species associated with pyridine nitrogen and specific interactions with each other have been determined. The agent synthesis and recycling steps are straightforward. The recyclability of the agent is achieved due to the reversible nature of the linker bonding with Br2 and HBr. This unique feature makes the composite the first, to knowledge, brominating agent that readily traps HBr without losing its properties. The presented composite can become a valuable addition to the group of mild, reusable, and multifunctional brominating agents. CAU‐10‐PDC metal‐organic framework readily absorbs Br2 vapors forming a new mild brominating agent. Rietveld refinement is used to determine the positions of the trapped bromine species in the MOF pore. Activated aromatics bromination is shown. The MOF reversible bonding nature with Br2 and the side‐forming HBr makes the MOF a useful and reusable container for Br2 and allows trapping HBr .

Use of halogenated flame retardants continues despite health and environmental concerns Halogenated flame retardants are used widely in consumer products such as carpets, textiles, and electronics to reduce the risk of fire. It has been known for more than 20 years that these compounds can leach into the environment, with particularly high concentrations recorded in fish and marine mammals. Concerns have also been raised about carcinogenic and endocrine-disrupting effects in humans. Some brominated flame retardants—in particular, polybrominated diphenyl ether (PBDE) commercial mixtures and hexabromocyclododecane (HBCD)—have been banned or phased out in some jurisdictions, and the possible use of alternative flame retardants has been investigated. Yet, over the past 20 years, global production of flame retardants has continued to rise without a decrease in halogenated flame retardant production. It is time for a critical evaluation of flame retardant use.

Vanadium(IV) oxido complex of 1-Phenyl-1,3-butanedione [V IV O(bzac) 2 ] ( 1 ) was prepared, characterized, and heterogenized onto APTMS modified graphene oxide, as well as imidazole modified polystyrene beads. Graphene oxide supported complex GO-APTMS-[V IV O(bzac) 2 ] ( 2 ) and polymer anchored complex PS-im-[V IV O(bzac) 2 ] ( 3 ) were used for the oxidative bromination of a number of small organic molecules and oxidation of a series of thioethers. Both 2 and 3 evolve as excellent heterogeneous catalysts. The nature of solid support does not impact substrate conversion (%) during the oxidative bromination of salicylaldehyde, phenol, or styrene, whereas it influences the substrate conversion (%) as well as the product selectivity (%) during the oxidation of thioethers. Graphic Abstract

The integration of synthetic and biological catalysis enables new approaches to the synthesis of small molecules by combining the high selectivity of enzymes with the reaction diversity offered by synthetic chemistry. While organohalogens are valued for their bioactivity and utility as synthetic building blocks, only a handful of enzymes that carry out the regioselective halogenation of unactivated C s p 3 − H bonds have previously been identified. In this context, we report the structural characterization of BesD, a recently discovered radical halogenase from the Fe II /α-ketogluturate-dependent family that chlorinates the free amino acid lysine. We also identify and characterize additional halogenases that produce mono- and dichlorinated, as well as brominated and azidated, amino acids. The substrate selectivity of this new family of radical halogenases takes advantage of the central role of amino acids in metabolism and enables engineering of biosynthetic pathways to afford a wide variety of compound classes, including heterocycles, diamines, α-keto acids and peptides. Structural characterization of the amino-acid-modifying radical halogenase BesD and identification of new members of this protein family provides insight into the enzymatic mechanism and enables biocatalytic production of halogenated amino acids.