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Exploration of elementary reactions in organometallic catalysis is an important method with which to discover new reactions. In this article, we report a gold(I)‐catalyzed iodo‐alkynylation of benzyne involving the merging of challenging migratory insertion and an oxidative addition process in gold catalytic cycle. A wide range of structurally diverse alkynyl iodides are good coupling partners in this iodo‐alkynylation transformation. Both aliphatic and aromatic alkynyl iodides can react with benzynes smoothly to afford highly functionalized 1,2‐disubstituted aromatics in moderate to good yields. Its good functional group compatibility and late‐stage application of complex molecules demonstrate its synthetic robustness. Studies of the mechanism reveals the feasibility of oxidative addition and the DFT calculations demonstrate the possible migratory insertion of benzyne into AuIII‐carbon bonds in the AuI/AuIII redox catalytic cycle, representing an important step towards an elementary reaction in gold chemistry research. [ABSTRACT FROM AUTHOR]

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Abstract: The first transition‐metal‐free, site‐specific umpolung trifluoromethylthiolation of tertiary alkyl ethers has been developed, achieving the challenging tertiary C(sp3)–SCF3 coupling under redox‐neutral conditions. The synergism of organophotocatalyst 4CzIPN and BINOL‐based phosphorothiols can site‐selectively cleave tertiary sp3 C(sp3)–O ether bonds in complex molecules initiated by a polarity‐matching hydrogen‐atom‐transfer (HAT) event. The incorporation of several competing benzylic and methine C(sp3)−H bonds in alkyl ethers has little influence on the regioselectivity. Selective difluoromethylthiolation of C−O bonds has also been achieved. This represents not only an important step forward in trifluoromethylthiolation but also a promising means for site‐selective C−O bond functionalization of unsymmetrical tertiary alkyl ethers. [ABSTRACT FROM AUTHOR]

Abstract: The first catalytic inverse hydroboration of imines with N‐heterocyclic carbene (NHC) boranes has been realized by means of cooperative organocatalysis and photocatalysis. This catalytic combination provides a promising platform for promoting NHC‐boryl radical chemistry under sustainable and radical‐initiator‐free conditions. The highly important functional‐group compatibility and possible application in late‐stage hydroborations represent an important step forward to an enhanced α‐amino organoboron library. [ABSTRACT FROM AUTHOR]

The remote radical migration strategy has gained considerable momentum. During the past three years, we have witnessed the rapid development of sustainable and practical C–C and C–H bond functionalization by means of long-distance 1,n-radical migration (n = 4, 5, 6) events. Its advent brings our chemical community a new platform to deal with the challenging migration transformations and thus complements the existing ionic-type migration protocols. In this review, the recent achievements in distal radical migration triggered C–C and C–H bond functionalization are summarized. [ABSTRACT FROM AUTHOR]

An operationally green, electron-catalyzed, photochemical tandem carbodifluoroalkylation/radical cyclization of enol ethers is disclosed. The reactions occur via addition of difluoroacyl radicals to methylene-2-oxazolines and subsequent intramolecular base-promoted homolytic alkyl substitution (BHAS) of the intermediate oxyl-alkyl radicals. Initiation of the radical chain reaction is best achieved with a commercially available and cheap organic base, and readily accessible visible light is used as the energy source. [ABSTRACT FROM AUTHOR]

A new ( S)-binaphthalene-based polymer ( P- 1) was synthesized by the polymerization of 5,5′-((2,5-dibutoxy-1,4-phenylene)bis(ethyne-2,1-diyl))bis(2-hydroxy-3-(piperidin-1-ylmethyl) benzaldehyde ( M- 1) with ( S)-2,2′-dimethoxy-(1,1′-binaphthalene)-3,3′-diamine ( M- 2) through the formation of a Schiff base; the corresponding chiral polymer ( P- 2) could be obtained by the reduction of polymer P- 1 with NaBH4. Chiral polymer P- 1 exhibited a remarkable 'turn-on' fluorescence-enhancement response towards ( D)-phenylalaninol and excellent enantioselective recognition behavior with enantiomeric fluorescence difference ratios ( ef) as high as 8.99. More importantly, chiral polymer P- 1 displays a bright blue fluorescence color change upon the addition of ( D)-phenylalaninol under a commercially available UV lamp, which can be clearly observed by the naked eye. On the contrary, chiral polymer P- 2 showed weaker enantioselective fluorescence ability towards the enantiomers of phenylalaninol. [ABSTRACT FROM AUTHOR]

A highly efficient, AgI/K2S2O8-mediated regioselective phosphonation reaction has been developed by using electron-deficient directing groups. These phosphonation reactions were performed with N, N-dialkylbenzamides, N, N-dialkylbenzenesulfonamides, and nitrobenzene. This method has a broad substrate scope and offers facile construction of C-P bonds. [ABSTRACT FROM AUTHOR]

Hoch funktionalisierte Diazoverbindungen entstehen durch die Titelreaktion in guten Ausbeuten und mit hervorragenden Enantioselektivitäten (siehe Schema; Boc=tert ‐ Butoxycarbonyl). Ausgehend von den Produkten waren zahlreiche optisch reine Stickstoffheterocyclen rasch zugänglich. Das entscheidende Merkmal des Prozesses ist der Einsatz von 2,2,2 ‐ Trifluorethyldiazoacetat als leistungsfähiges nucleophiles Reagens. [ABSTRACT FROM AUTHOR]

Abstract: Crmation was realized through the three-component reaction of an amine, an aldehyde and a dialkylphosphite catalyzed by gold complex. The corresponding α-aminophosphonates were afforded in one-pot reaction with high yields under mild conditions. [Copyright &y& Elsevier]

A rapid and efficient procedure for the synthesis of di�arylmethanols has successfully been achieved by the aryl transfer to aldehydes using the ArB(OH)2-GaMe3 combined systems in excellent yields (up to 98%) at room temperature. [ABSTRACT FROM AUTHOR]

A new synthetic strategy for C–C bond formation has been developed via a free radical cascade process under metal-free conditions. Activation of inert C(sp3)–H/elimination of SO2/C–C bond formation were achieved in sequence in this system. [ABSTRACT FROM AUTHOR]

An elegant approach to quaternary oxindole formation has been developed through a room temperature decarboxylation/radical C–H functionalization by visible-light photoredox catalysis. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed decarboxylative C2-acylation of indoles with α-oxocarboxylic acids was achieved. This protocol represents a novel and complementary approach to 2-aroylindoles. [ABSTRACT FROM AUTHOR]

Abstract: A facile and efficient protocol for the synthesis of amides has been developed in the absence of transition metals. The reaction was performed with a catalytic amount of n-Bu4NI and aqueous TBHP as an oxidant. Various alcohols with N,N-disubstituted formamides were examined to furnish the desired products in good yields. [Copyright &y& Elsevier]

Abstract: Two chiral salan–Cu(II) complexes, dinuclear {[(C28H26CuN2O2)2 ·2CH3OH∙CH3COOH] (1)} and mononuclear {[C56H55CuN4O4∙½CH3OH∙CH3COOH∙H2O] (2)} were synthesized and structurally characterized. The complex 1 was obtained with the ratio 1:1.2 of the metal source and the ligand, in which the two copper atoms were bridged by μ–O atoms forming a four-membered binuclear Cu2O2 square–planar geometry. However, using two equivalents of the ligand led to the formation of the complex 2, in which one copper atom coordinated with two salan ligands bound in a five-coordinate square–pyramidal. The asymmetric Henry reaction was studied by these in situ formed complexes. The complex 1 provided moderate to high enantioselectivities (up to 83%) when the reaction was carried out in EtOH at room temperature for 48h, whereas the complex 2 gave a modest enantioselectivity. [Copyright &y& Elsevier]

Abstract: The polymer was synthesized by the polymerization of 4,4′-((4-iodophenoxy)methyl)-2,2′-bipyridine (M-1) with 4,7-diethynylbenzo[2,1,3]-thiadiazole (M-2) via Pd-catalyzed Sonogashira reaction. The fluorescence responses of the polymer towards various transition metal ions were investigated by fluorescence spectra and UV–Vis spectra. The polymer shows green fluorescence under ultraviolet lamp, which can be quenched by Cu2+ completely due to the heavy metal effect. The results suggested that the polymer can be used as a Cu2+-selective sensor via a naked eyes detecting mode. [Copyright &y& Elsevier]

Abstract: A novel BINOL-pyrene derivative sensor 1 for Ag+ and Hg2+ incorporating the triazole moieties and pyrenes was synthesized via click reaction. Binding of Ag+ ion induces the formation of 1:1 Ag+–1 chelating complex, and occurs in a ratiometric manner through an enhanced monomer and declining excimer emission, which make it possible to ratiometrically detect Ag+. The competitive experiment shows 1 can be used as an Ag+ specific fluorescence sensor over a wide range of competing cations. In the meanwhile, the sensor 1 was found to be selectively quenched by only Hg2+ at both monomer and excimer emission. Furthermore, we obtained evidences for different fluorescence signaling behaviors with Ag+ and Hg2+ by 1H NMR titration experiments. [Copyright &y& Elsevier]

Abstract: The novel (S)-BINOL-based sensor 1 incorporating triazole moieties could be obtained by click reaction. The results show that 1 can exhibit excellent fluorescence response behaviors toward Hg2+ (selective switching-off) and Ag+ (selective switching-on) without interference from other metal ions, which functions as a molecular switch. This work can expand the application of click reaction in design and synthesis of the novel fluorescence sensor molecules. [Copyright &y& Elsevier]

Abstract: The asymmetric pinacol coupling of aromatic aldehydes by chiral salan–vanadium complexes as effective catalysts is reported. Chiral 1,2-diols were obtained with high diastereoselectivities (up to 90/10) and moderate to high enantioselectivities (up to 82% ee). The possible mechanism of the pinacol coupling reaction is also discussed. [Copyright &y& Elsevier]

The reaction has a broad substrate scope, thus tolerating diversely functionalized styrene derivatives as well as cyclic and acyclic internal alkenes and various N-arylated bromodifluoroacetamides, but no N-alkylated derivatives thereof. [ABSTRACT FROM AUTHOR]

In the presence of a cinchona alkaloid derived tertiary amine catalyst phosphorous ylides (I) undergo efficient asymmetric allylic substitution of O-Boc protected Morita-Baylis-Hillman products (II) to yield the chiral pentadiene (IV) after reaction of the allylic adducts with formaldehyde. [ABSTRACT FROM AUTHOR]

The title reaction is performed with N,N-dialkylbenzamides, N,N-dialkylbenzenesulfonamides, and nitrobenzene (XII). [ABSTRACT FROM AUTHOR]