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Recent years have witnessed a renaissance of organic electrochemistry since the cheap, safe, sustainable electron could be employed as a traceless redox agent to facilitate redox conversions. Additionally, divergent selectivity could be achieved by tuning the potential or current of the electrochemical reaction. Compared to electrooxidation or electroreduction reactions, paired electrolysis represents a more practical and energy‐efficient strategy that delivers the products by making use of both anodic and cathodic reactions simultaneously. This mini‐review summarized the breakthroughs and recent advances in this fascinating field and mainly is divided into three parts: parallel, sequential, and convergent paired electrolysis. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Electrochemical nickel‐catalyzed syntheses of triphenylenes by a) reductive trimerization of ortho‐dibromobenzenes or ortho‐bromoarylsulfurofluoridates, or b) reductive cross‐coupling of ortho‐dibromobenzenes to 2,2'‐diiodobiphenyls, are described. The former provides a practical means for the construction of triphenylene derivatives in up to 87% isolated yield at room temperature. For 1,2‐dihalo‐3‐methylbenzenes and related ortho‐trisubstituted substrates, trimerizations proceed with high substrate‐controlled regioselectivity for the non‐C3h symmetric triphenylene isomer. [ABSTRACT FROM AUTHOR]

A novel strategy for the N‐arylation of NH‐sulfoximines has been developed by merging nickel catalysis and electrochemistry (in an undivided cell), thereby providing a practical method for the construction of sulfoximine derivatives. Paired electrolysis is employed in this protocol, so a sacrificial anode is not required. Owing to the mild reaction conditions, excellent functional group tolerance and yield are achieved. A preliminary mechanistic study indicates that the anodic oxidation of a NiII species is crucial to promote the reductive elimination of a C−N bond from the resulting NiIII species at room temperature. [ABSTRACT FROM AUTHOR]

An intermolecular hydroalkylative dearomatization of naphthalenes with commercially available α‐amino acids is achieved via visible‐light photoredox catalysis. With an organic photocatalyst, a series of multi‐substituted 1,2‐dihydronaphthalenes are obtained in good‐to‐excellent yields. Intriguingly, by tuning the substituents at the C2 position of naphthalenes, formal dearomative [3+2] cycloadditions occur exclusively via a hydroalkylative dearomatization–cyclization sequence. This overall redox‐neutral method features mild reaction conditions, good tolerance of functionalities, and operational simplicity. Diverse downstream elaborations of the products are demonstrated. Preliminary mechanistic studies suggest the involvement of a radical–radical coupling pathway. [ABSTRACT FROM AUTHOR]

A novel strategy for asymmetric Shono‐type oxidative cross‐coupling has been developed by merging copper catalysis and electrochemistry, affording C1‐alkynylated tetrahydroisoquinolines with good to excellent enantioselectivity. The use of TEMPO as a co‐catalytic redox mediator is crucial not only for oxidizing a tetrahydroisoquinoline to an iminium ion species but also for decreasing the oxidation potential of the reaction. A novel bisoxazoline ligand is also reported. [ABSTRACT FROM AUTHOR]

A highly regioselective Ni‐catalyzed electrochemical reductive relay cross‐coupling between an aryl halide and an alkyl halide has been developed in an undivided cell. Various functional groups are tolerated under these mild reaction conditions, which provides an alternative approach for the synthesis of 1,1‐diarylalkanes. [ABSTRACT FROM AUTHOR]

Transition‐metal‐catalyzed coupling reactions are useful tools for synthesizing aryl sulfur compounds. However, conventional transition‐metal‐catalyzed thiolation of aryl bromides and chlorides typically requires the use of strong base under elevated reaction temperature. Herein, we report the first examples of nickel‐catalyzed electrochemical thiolation of aryl bromides and chlorides in the absence of an external base at room temperature using undivided electrochemical cells. It's electrifying! Nickel‐catalyzed thiolation of aryl halides was achieved in the absence of an external base and at room temperature through an electrochemical reaction in undivided electrochemical cells. This method provides a practical approach for the construction of aryl and heteroaryl C−S bonds. [ABSTRACT FROM AUTHOR]

Hobo/Activator/Tam3 (hAT) superfamily transposons occur in plants and animals and play a role in genomic evolution. Certain hAT transposons are active and have been developed as incisive genetic tools. Active vertebrate elements are rarely discovered; however, Tgf2 transposon was recently discovered in goldfish (Carassius auratus). Here, we found that the endogenous Tgf2 element can transpose in goldfish genome. Seven different goldfish mRNA transcripts, encoding three lengths of Tgf2 transposase, were identified. Tgf2 transposase mRNA was detected in goldfish embryos, mainly in epithelial cells; levels were high in ovaries and mature eggs and in all adult tissues tested. Endogenous Tgf2 transposase mRNA is active in mature eggs and can mediate high rates of transposition (>30%) when injected with donor plasmids harboring a Tgf2 cis-element. When donor plasmid was coinjected with capped Tgf2 transposase mRNA, the insertion rate reached >90% at 1 yr. Nonautonomous copies of the Tgf2 transposon with large-fragment deletions and low levels of point mutations were also detected in common goldfish. Phylogenetic analysis indicates the taxonomic distribution of Tgf2 in goldfish is not due to vertical inheritance. We propose that the goldfish Tgf2 transposon originated by recent horizontal transfer and maintains a highly native activity [ABSTRACT FROM AUTHOR]

One new guaianolide, anomalactone A (), and one new norcadinane sesquiterpene, anomallenodiol (), along with two germacranolides, anomalactones B and C ( and , resp.), were isolated from the aerial part of Artemisia anomala S. . Their structures were determined on the basis of extensive spectroscopic analyses. [ABSTRACT FROM AUTHOR]

Four polymers (P0–P3) containing peptide chain as polymer backbone were synthesized by condensation reaction with bis(trichloromethyl)carbonate and triethylamine. The chemical structures of the monomers M0–M3 were confirmed by FTIR and 1H‐NMR. The structure–property relationships of the monomers and polymers are discussed. Their phase behavior and optical properties were investigated by differential scanning calorimetry, thermogravimetric analysis, and polarizing optical microscopy. Monomers M1–M3 and polymers P1–P3 displayed cholesteric phases. The results demonstrated that the melt temperature and clear point of monomers (M1–M3) and polymers (P1–P3) decreased with the increase of the flexible spacer length in the side‐chain, and the mesophase temperature range of the polymers increased with the increase of the flexible spacer length. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 [ABSTRACT FROM AUTHOR]

Side‐chain liquid crystalline ionomers containing M1 (4‐allyoxybenzoyloxy‐4′‐amylbenzoyloxy biphenyl) as mesogenic units and M2 (4‐undecylenicoxy‐4′‐phenylazobenzene sulfonic acid) as ionic units were synthesized by graft copolymerization. Their liquid crystalline properties were characterized by differential scanning calorimetry, polarizing optical microscopy, and X‐ray diffraction measurements. The results showed that introduction of nonmesogenic ionic units into polymeric structure could cause additional reduction of the clearing point of the ionomers, compared with the corresponding nonion polymers. When the content of ionic units increased to 8.5%, the ionic clusters and mesogens in the ionomers may be dispersed each other to form multiple blocks, but the introduction of ionic groups in LCIs did not change their mesogenic type. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 304–309, 2007 [ABSTRACT FROM AUTHOR]

Organic electrochemistry has a rich history in organic synthesis and has been considered as a promising alternative to traditional chemical oxidants and reductants because it obviates the use of stoichiometric amount of dangerous and toxic reagents. In particular, the electrochemical C—H bonds functionalization is one of the most desirable approaches for the construction of carbon–carbon (C—C) and carbon–heteroatom (C—X) bonds. This review summarizes the substantial progress made in the last few years in C—H functionalization via organic electrochemistry. It is divided into sections on C—C, C—N, C—O, C—S, C–Halogen and C—P bond formation. [ABSTRACT FROM AUTHOR]

Aliphatic amides are selectively functionalized at the γ- and δ-positions through directed radical 1,5 and 1,6 H-abstractions, respectively. [ABSTRACT FROM AUTHOR]

A novel protocol for the title synthesis via a palladium-catalyzed C-H activation/cyclization sequence is developed. [ABSTRACT FROM AUTHOR]

The general and highly selective title reaction affords products, which are difficult to access easily using traditional approaches. [ABSTRACT FROM AUTHOR]

An enantioselective variant of the Heck reaction that delivers β, γ, or δ-aryl carbonyl products [cf. [ABSTRACT FROM AUTHOR]

Review: ca. 150 refs. [ABSTRACT FROM AUTHOR]

In the title compound, [Cu(C9H5N2O2)2(H2O)2], the CuII ion lies on an inversion centre and has an elongated centrosymmetric octahedral environment, equatorially trans-coordinated by two N, O-bidentate quinoxaline-2-carboxylate ligands and axially coordinated by two water O atoms. Symmetry-related molecules are linked by strong O—H...O hydrogen bonds, involving the uncoordinated carboxyl O atom of the carboxylate group and the coordinated water molecules, to form a two-dimensional network. Weak intermolecular C—H...N interactions also stabilize the crystal structure. [ABSTRACT FROM AUTHOR]

The title Schiff base compound, C18H21N3O2, was synthesized by a condensation reaction of 4-hydroxybenzaldehyde with diethylenetriamine. The crystal structure determination reveals that one of the terminal hydroxy groups is deprotonated while the imino group of the molecule is protonated; thus the compound is a zwitterion. The two terminal benzene rings are nearly parallel to one another, with a dihedral angle of 9.94 (6)°. Intermolecular O—H...O and N—H...O hydrogen bonding helps to stabilize the crystal structure. [ABSTRACT FROM AUTHOR]

The title molecule, C14H8Cl2N2O2, is a trans-azobenzene which has a crystallographic inversion center at the mid-point of the N=N bond [N=N = 1.228 (4) Å]. There are neither hydrogen bonds nor π–π interactions between the aromatic rings, and the crystal structure is stabilized by van der Waals interactions. [ABSTRACT FROM AUTHOR]

In the title compound, C19H15NO2, the norbornene is fused to a cyclodicarbonimide, and the naphthyl ring is directly linked to the N atom. The crystal packing is stabilized by two kinds of intermolecular C—H...O hydrogen bonds and one intramolecular C—H...N hydrogen bond as well as by C—H...π-ring interactions. [ABSTRACT FROM AUTHOR]

Single crystals of Ba6Cs2InxGa10-xSe20 Cl4 with x = 2 (I) and 1 (II) are prepared by solid state reaction of stoichiometric amounts of CsCl, BaCl2, Ba, In, Ga, and Se (graphite crucible in evacuated silica tubes, 1172 K, 100 h). [ABSTRACT FROM AUTHOR]