Search

The Pd‐catalyzed vinylation reactions of aryl iodides using 1,2‐dibromoethane is developed for the synthesis of styrenes and stilbenes. In these reactions, vinyl bromide is generated from 1,2‐dibromoethane and then undergoes reductive cross‐coupling with aryl iodides, affording styrene products. Under slightly modified reaction conditions, styrenes can continue reacting with vinyl bromide to form E‐stilbenes, which provides a one‐pot synthetic method for stilbenes. Alcohols, including iso‐propanol and methanol, are employed as the reductant in these reductive cross‐coupling reactions. [ABSTRACT FROM AUTHOR]

Summary: With the continuous improvement of the national design standards of urban road lighting system, the intelligent, automatic, and remote management of urban street lighting system by using modern computer technology and the rapid development of Internet of things technology have become one of the important symbols of modern city. This paper mainly studies the circuit system based on cloud edge fusion outdoor intelligent light networking. Based on the development of wireless networking technology of new light source and sensor and data communication and processing technology of Internet of things, this paper analyzes the development trend and support status of intelligent lighting system, summarizes the overall demand for intelligent lighting system, and proposes a complete set of communication interface software, data‐processing software, operation management software, and street lamp controller group system architecture. The street lamp controller realizes the short distance wireless network through ZigBee technology and realizes the communication interaction of control and state acquisition data by GPRS wireless transmission technology. This paper tests the real‐time performance, packet loss rate, and stability of sensor data service provided by sensor nodes in the system. Finally, the monitoring experiments of the lighting circuit system are carried out, and the status of all street lamps in the centralized controller of street lamps is inquired every 5 min for 20 times. In these 20 times, the success rate of the first return of the switch state of the lamp is 100%, while that of the current and voltage is 98.6%. The experimental results show that the design of the lighting circuit system is feasible and the system runs stable and realizes the intelligent monitoring of the lighting system. [ABSTRACT FROM AUTHOR]

Two methods for the synthesis of norbornane‐fused indanes via palladium‐catalyzed three‐component reactions of iodoarenes, norbornenes, and CH2Br2 or α‐diazoesters have been developed. In the reactions, three C−C bonds were constructed and a wide range of norbornane‐fused indanes could be synthesized. The reactions with α‐diazoesters proceeded with a high degree of diastereoselectivity and indanes bearing an all‐carbon quaternary center were formed. The products obtained in the reactions of 1,4‐dihydro‐1,4‐epoxynaphthalene can be converted to fluorenes, providing an alternative way to access fluorene derivatives. [ABSTRACT FROM AUTHOR]

An efficient approach for the synthesis of benzimidazoles has been developed through the Pd‐catalyzed amination of 2‐iodobenzimines with diaziridinone. A wide range of 2‐(hetero)aryl benzimidazloes are synthesized in good to excellent yields. The reactions likely involve C,C‐palladacycles derived from 2‐iodobenzimines as the key intermediate, and the palladacycles reacted with diaziridinone to form benzimidazoles. [ABSTRACT FROM AUTHOR]

An approach for the synthesis of benzofulvenes has been developed through palladium‐catalyzed sequential three‐component reactions. The reactions likely involve C,C‐palladacycles as the key intermediates. The palladacycles are generated through cascade reactions of aryl halides and alkynes, and then reacted with CH2Br2 to form benzofulvenes as the final products. [ABSTRACT FROM AUTHOR]

Abstract: The reactions of various C,C‐palladacycles that were generated through the C−H activation of aryl halides with disilanes have been studied. The reaction of arylnorbornyl palladacycles, which were generated through a Catellani reaction, with hexamethyldisilane proceeded very efficiently to afford disilylated products. Palladacycles that were obtained through the remote C−H activation of aryl halides that contained a styrene moiety with an ether linkage also underwent a disilylation reaction with hexamethyldisilane. Furthermore, the reactions of dibenzopalladacyclopentadienes, which were generated from 2‐iodobiphenyls, with diphenyltetramethyldisilane were also investigated and a range of 2‐iodobiphenyls were disilylated in moderate yields. [ABSTRACT FROM AUTHOR]

Abstract: A highly efficient palladium‐catalyzed disilylation reaction of aryl halides through C−H activation has been developed for the first time. The reaction has broad substrate scope. A variety of aryl halides can be disilylated by three types of C−H activation, including C(sp2)−H, C(sp3)−H, and remote C−H activation. In particular, the reactions are also unusually efficient. The yields are essentially quantitative in many cases, even in the presence of less than 1 mol % catalyst and 1 equivalent of the silylating reagent under relatively mild conditions. The disilylated biphenyls can be converted into disiloxane‐bridged biphenyls. [ABSTRACT FROM AUTHOR]

Abstract: A facile and efficient approach has been developed for the synthesis of carbazoles from 2‐iodobiphenyls and diaziridinone under palladium catalysis. A wide range of carbazoles were synthesized in good to excellent yields, and indole derivatives were obtained by using styrenes as the substrate. The palladacycles obtained from 2‐iodobiphenyls acted as the key intermediate, and the reaction should proceed via a tandem Pd‐catalyzed C−H activation/dual C−N bond formation sequence. [ABSTRACT FROM AUTHOR]

Utilizing halogens as traceless directing goups represents an attractive strategy for C−H functionalization. A two C−H alkylation system, initiated by the oxidative addition of organohalides to Pd0, has been developed. The first reaction involves an intermolecular alkylation of palladacycles to form C(sp3)−C(sp2) bonds followed by C(sp2)−H activation/cyclization to deliver alkylated benzocyclobutenes as the final products. In the second reaction, two C−C bonds are formed by the reaction of palladacycles with CH2Br2, and provides a facile and efficient method for the synthesis of indanes. The alkylated benzocyclobutene products can be transformed into tricyclic hyrocarbons, and the indane derivatives are essential structural motifs in bioactive and odorant molecules. [ABSTRACT FROM AUTHOR]

An efficient palladium-catalysed ortho-C-H olefination of α,α-difluorophenylacetic acid derivatives using 8-aminoquinoline as a bidentate directing group has been developed. A range of olefinated arenes can thus be synthesized in a concise way. This reaction provides an easy and straightforward route to a panel of difluoromethylated arene analogues in moderate to good yields, with a satisfactory tolerance of common functional groups. Transformation of the products into a variety of other difluoromethylene-containing compounds demonstrates the utility of this method. [ABSTRACT FROM AUTHOR]

The first cross-coupling reaction between aryl silanes and aryl boronic acids is described. This transformation represents one of the very few examples of coupling reactions between two nucleophilic organometallic reagents and provides a new method for the formation of biaryl compounds. The successful development of this reaction was enabled by the use of commercially available 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (BINAP) as the ligand. A small amount of BINAP (3 mol %) was sufficient to suppress the formation of the homocoupling products, and the reaction yielded the cross-coupling products with high selectivity under mild conditions, even when the ratio of the two coupling partners was 1:1. [ABSTRACT FROM AUTHOR]

As a widely existing functional group in organic molecules, the carboxyl group has numerous advantageous characteristics such as great convenience for further transformation, relatively low toxicity and cost, and weak coordination to transition metal catalysts, which render it an attractive directing group in transition metal-catalyzed CH bond functionalization reactions. This review surveys transition metal-catalyzed CH bond functionalization reactions directed by carboxylates, including carbon-carbon, carbon-oxygen, and other carbon-heteroatom bond formation reactions. Reactions directed by the acidic N-arylamides, which are derived from carboxylic acids and have a directing mode similar to that of carboxylates, are also presented here. [ABSTRACT FROM AUTHOR]

The copper-catalyzed decarboxylative methylation of aromatic carboxylic acids was developed by using PhI(OAc)2 to provide a new strategy for the methylation of aryl acids through the decarboxylation of alkyl acids. The mechanism and the roles of each reactant in the reaction were investigated extensively. [ABSTRACT FROM AUTHOR]

The cover image is based on the Original Article I Molecular investigation in Chinese patients with primary carnitine deficiency i by Yanghui Zhang et al., https://doi.org/10.1002/mgg3.901. GRAPH. [Extracted from the article]

Background: Primary carnitine deficiency (PCD) is an autosomal recessive disorder of carnitine transportation caused by mutations in the SLC22A5 that lead to low serum carnitine levels and decreased intracellular carnitine accumulation. Characteristic clinical findings are hypoketotic hypoglycemia and skeletal and cardiac myopathy. Objective: To genetically diagnose 24 unrelated Chinese patients with PCD, including 18 infants and six adults. Methods: The entire coding region and the intron–exon boundaries of SLC22A5 were amplified by polymerase chain reaction (PCR). In silico analyses and reverse transcription‐polymerase chain reaction (RT‐PCR) were used to predict variants' impact on protein structure and function. Results: Disease‐causing variants in the SLC22A5 were identified in all 24 subjects, and c.288delG, c.495C>A, c.774_775insTCG, c.824+1G>A, and c.1418G>T were novel. The novel variant c.824+1G>A caused a truncated protein p.Phe276Tyrfs*8. Conclusions: We identified 13 variants in the SLC22A5 in 24 PCD patients, and five of these variants are novel mutations. c.824+1G>A was confirmed to alter mRNA splicing by reverse transcription PCR. Furthermore, our findings broaden the mutation spectrum of SLC22A5 and the understanding of the diverse and variable effects of PCD variants. [ABSTRACT FROM AUTHOR]

The inside cover picture, provided by Yanghui Zhang and co‐workers, illustrates the domino reaction of aryl iodides, alkynes, and CH2Br2 that they have developed. The domino process involves migratory insertion of arylpalladium(II) species to alkynes, intramolecular C–H activation to form C,C‐palladacycles, alkylation by CH2Br2 to give indenes, and reaction with a second molecule of CH2Br2 to afford benzofulvenes as the final products. The reaction represents an innovative approach for the synthesis of benzofulvenes. Details can be found in the communication on pages 4480–4484 (B. Zhou, Z. Wu, W. Qi, X. Sun, Y. Zhang, Adv. Synth. Catal. 2018, 360, 4480–4484; DOI: 10.1002/adsc.201801141). [ABSTRACT FROM AUTHOR]

Review: [68 refs. [ABSTRACT FROM AUTHOR]

A correction to the article "Carboxylate-Directed C—H Functionalization" that was published in the 2014 issue is presented.

The copper-catalyzed decarboxylative methylation of aromatic carboxylic acids was developed by using PhI(OAc)2 to provide a new strategy for the methylation of aryl acids through the decarboxylation of alkyl acids. The mechanism and the roles of each reactant in the reaction were investigated extensively. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Copper-Catalyzed Decarboxylative Methylation of Aromatic Carboxylic Acids with PhI(OAc)2" by S. Pan and other, published in the periodical "European Journal of Organic Chemistry" in 2014.