The nickel-catalyzed cross-coupling reactions of neopentyl arenesulfonates with arylmagnesium bromides, involving nucleophilic aromatic substitution of alkyloxysulfonyl groups by aryl nucleophiles, take place in high yields. Optimal efficiencies are obtained by adding 3 + 2 equiv of the Grignard reagent to a mixture of dppfNiCl(2) and the sulfonate in refluxing THF. Neopentyl arenesulfonates are useful sources of the electrophilic aryl groups in these transition metal-catalyzed cross-coupling reactions. Aryl sulfonates are inappropriate due to their ambident reactivity under the reaction conditions. This new cross-coupling reaction can be used for the creative elimination of alkyloxysulfonyl groups from aromatic compounds and for the preparation of unsymmetric terphenyls and oligophenyls.

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A method to control activation of a DNA nanodevice by supplying a complementary\ud DNA (cDNA) strand from an electro-responsive nanoplatform is reported. To develop\ud functional nanoplatform, hexalayer nanofilm is precisely designed by layer-by-layer\ud assembly technique based on electrostatic interaction with four kinds of materials:\ud Hydrolyzed poly(β-amino ester) can help cDNA release from the film. A cDNA is\ud used as a key building block to activate DNA nanodevice. Reduced graphene oxides\ud (rGOs) and the conductive polymer provide conductivity. In particular, rGOs efficiently\ud incorporate a cDNA in the film via several interactions and act as a barrier. Depending\ud on the types of applied electronic stimuli (reductive and oxidative potentials), a\ud cDNA released from the electrode can quantitatively control the activation of DNA\ud nanodevice. From this report, a new system is successfully demonstrated to precisely\ud control DNA release on demand. By applying more advanced form of DNA-based\ud nanodevices into multilayer system, the electro-responsive nanoplatform will expand\ud the availability of DNA nanotechnology allowing its improved application in areas\ud such as diagnosis, biosensing, bioimaging, and drug delivery

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Chalcone derivatives afford several pharmacological activities. However, a general synthetic method for 2',4'‐dihydroxy‐6'‐methoxy‐3',5'‐dimethylchalcone (DMC) derivatives has not been reported thus far. To address this, the preparation of 4',6'‐dimethoxy‐2'‐hydroxy‐3',5'‐dimethylchalcone (MDMC) derivatives, modified compounds of DMC, in excellent overall yields is reported herein. These compounds have recently attracted growing attention due to their various pharmacological activities. Di‐O‐methyl‐dimethylphloroacetophenone, the key intermediate containing the B‐ring moiety, was fabricated by four efficient reaction steps from commercially available phloroglucinol in a 50.1% isolated yield overall. Our synthetic route, which constructs the chalcone skeleton in the final stage via a Claisen–Schmidt condensation of the key intermediate with the desired benzaldehyde derivative, can rapidly produce a vast library of DMC derivatives.

Application of a novel sulfonate-based traceless multifunctional linker system using pentaerythritol as a tetrapodal soluble support was demonstrated using liquid-phase parallel and combinatorial preparation of biphenyl and terphenyl compounds. Nickel-catalyzed reactions of pentaerythritol tetrakis(arenesulfonate)s with arylmagnesium bromides generated the desired products in sufficient yields through reductive cleavage/cross-coupling of the C-S bond. Homogeneous pentaerythritol-supported reactions could be accomplished using less nucleophile with shorter reaction periods than could the corresponding heterogeneous polymer-supported reactions. This liquid-phase approach using a small polyfunctionalized support combines advantages of solution-phase and solid-phase syntheses by allowing high reactivity, high atom economy, simple isolation, and real-time monitoring of the reaction progress.

[reaction: see text] Neopentyl arenesulfonates were reacted with methyl and primary alkylmagnesium bromides in the presence of dppeNiCl(2), via the nucleophilic aromatic substitution of neopentyloxysulfonyl groups by the primary alkyl nucleophiles, to produce the corresponding alkylarenes in good yields. This result shows that the alkyloxysulfonyl group might be a suitable alternative to halides and triflate in some circumstances.