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The treatment of massive bone defects is still a significant challenge for orthopedists. Here we have engineered synthetic porous AuPd alloy nanoparticles (pAuPds) as a hyperthermia agent for in situ bone regeneration through photothermal therapy (PTT). After being swallowed by cells, pAuPds produced a mild localized heat (MLH) (40-43 °C) under the irradiation of a near-infrared laser, which can greatly accelerate cell proliferation and bone regeneration. Almost 97% of the cranial defect area (8 mm in diameter) was covered by the newly formed bone after 6 weeks of PTT. RNA sequencing analysis was used to obtain insight into the molecular mechanism of the MLH on cell proliferation and bone formation. These results demonstrated that the Wnt signaling pathway was involved in the MLH. This Letter provides a unique strategy with mild heat stimulation and high efficiency for in situ bone regeneration.

An unprecedented example of Pd-catalyzed difluoromethylation of aryl boronic acids with bromodifluoroacetate is described. The reaction proceeds under mild reaction conditions with hydroquinone and Fe(acac)3 as additives. Preliminary mechanistic studies reveal that a difluorocarbene pathway is involved in the reaction, which is unusual compared to the most traditional approaches. This reaction has advantages of high efficiency and excellent functional group compatibility, even toward bromide and hydroxy group, thus providing a useful protocol for drug discovery and development.

An efficient palladium-catalyzed Heck-type reaction of fluoroalkyl halides, including perfluoroalkyl bromides, trifluoromethyl iodides, and difluoroalkyl bromides, has been developed. The reaction proceeds under mild reaction conditions with high efficiency and broad substrate scope, and provides a general and straightforward access to fluoroalkylated alkenes which are of interest in life and material sciences., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A first example of Pd-catalyzed heteroaryldifluoromethylation of organoborons with bromodifluoromethylated heteroarenes has been described. The use of phosphine ligand PAd2(n-Bu)·HI is critical for the reaction efficiency. With use of this ligand, a wide range of aryl(heteroaryl)difluoromethanes were obtained with high efficiency. The notable features of this reaction are its broad substrate scope and excellent functional group compatibility, thus providing a facile protocol for application in drug discovery and development.

The palladium-catalyzed difluoroalkylation of aryl boronic acids with bromodifluoromethylphosphonate, bromodifluoroacetate, and further derivatives has been developed. This method provides a facile and useful access to a series of functionalized difluoromethylated arenes (ArCF2 PO(OEt)2 , ArCF2 CO2 Et, and ArCF2 CONR(1) R(2) ) that have important applications in drug discovery and development. Preliminary mechanistic studies reveal that a single electron transfer (SET) pathway may be involved in the catalytic cycle., (Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A first example of Pd-catalyzed gem-difluoroallylation of organoborons using 3-bromo-3,3-difluoropropene (BDFP) in high efficiency with high α/γ-substitution regioselectivity has been developed. The reaction can also be extended to substituted BDFPs and has advantages of low catalyst loading (0.8 to 0.01 mol %), broad substrate scope, and excellent functional group compatibility, thus providing a facile route for practical application in drug discovery and development.

A methyl(phenyl)sulfane-promoted direct olefination of polyfluoroarenes catalyzed by palladium has been reported. With use of this new thioether ligand, a high reaction efficiency and excellent E/Z ratio of desired olefinated polyfluoroarenes were obtained. This represents a first example of thioether promoted oxidative Heck reaction.

Simply id(all)ylic: a copper- and phosphine-ligand-free Pd-catalyzed direct allylation of electron-deficient polyfluoroarenes with allylic chlorides and the reaction mechanism are described. The simple catalytic system, broad substrate scope, and excellent functional-group compatibility of this protocol provides a useful and facile access to allylated polyfluoroarenes., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The first example of intermolecular regioselective α-arylation of heteroatom-substituted enones with polyfluoroarenes via twofold C-H bond functionalization using a palladium catalyst is reported. This approach provides rapid access to a wide range of α-fluoroarylated enones of interest in life science.

We report a Pd-catalyzed direct cross-coupling of electron-deficient polyfluoroarenes with heteroaromatic tosylates. The notable features of this reaction are its high reaction efficiency, excellent chemoselectivity, operational simplicity, and mild reaction conditions. We have applied this protocol to prepare the semiconducting materials in a highly efficient manner., (© 2011 American Chemical Society)

An efficient and practical method to a wide range of perfluorinated unsymmetrical diarylmethanes with good to excellent yields and high regioselectivities has been developed by Pd-catalyzed direct benzylation of highly electron-deficient perfluoroarenes; excellent compatibility of functional groups has also been established.

A palladium‐catalyzed reductive difluorocarbene transfer reaction that tames difluorocarbene to couple with two electrophiles has been developed, representing a new mode of difluorocarbene transfer reaction. The approach uses low‐cost and bulk industrial chemical chlorodifluoromethane (ClCF2H) as the difluorocarbene precursor. It produces a variety of difluoromethylated (hetero)arenes from widely available aryl halides/triflates and proton sources, featuring high functional group tolerance and synthetic convenience without preparing organometallic reagents. Experimental mechanistic studies reveal that an unexpected Pd0/II catalytic cycle is involved in this reductive reaction, wherein the oxidative addition of palladium(0) difluorocarbene ([Pd0(Ln)]=CF2) with aryl electrophile to generate the key intermediate aryldifluoromethylpalladium [ArCF2Pd(Ln)X], followed by reaction with hydroquinone, is responsible for the reductive difluorocarbene transfer. [ABSTRACT FROM AUTHOR]

The enantioselective construction of C–CF2R (R: alkyl or fluoroalkyl) bonds has attracted the attention of synthetic chemists because of the importance of chiral fluorinated compounds in life and materials sciences. Catalytic asymmetric fluoroalkylation has mainly been realized under organocatalysis and Lewis acid catalysis, with substrates limited to carbonyl compounds. Few examples using transition-metal catalysis exist, owing to side reactions including decomposition and isomerization of fluoroalkylating reagents. Herein we report umpolung asymmetric difluoroallylation of hydrazones with 3-bromo-3,3-difluoropropene (BDFP) under palladium catalysis. Difluoroallylation products having quaternary chiral carbon centers are afforded in good yields with high α/γ- and enantioselectivities. The usefulness of the reaction products is demonstrated and an inner-sphere mechanism of the reaction is proposed. The use of chiral N-heterocyclic carbene as ligand is the key for the selectivities as well as the productivity of the reaction. Installation of difluoroalkyl groups while also imparting stereochemical information is mostly only possible with organocatalytic methods that activate carbonyls. Here the authors show a method to perform an difluoroallylation of hydrazones, forming a masked amine stereocenter, via palladium- and N-heterocyclic-carbene catalysis. [ABSTRACT FROM AUTHOR]

Although important progress has been made in the fluoroalkylation reactions, the transition-metal-catalyzed carbonylative fluoroalkylation reaction remains challenging so far. Herein, we report the first example of a Pd-catalyzed carbonylation of difluoroalkyl bromides with (hetero)arylboronic acids under one atmosphere pressure of CO. The reaction can also be extended to the aryl potassium trifluoroborate salts. The advantages of this protocol are synthetic simplicity, broad substrate scope, and excellent functional group compatibility. The resulting difluoroalkyl ketones can serve as versatile building blocks for the synthesis of various useful fluorinated compounds. [ABSTRACT FROM AUTHOR]

A highly regio- and stereo-selective palladium-catalyzed gem-difluoroallylation of arylboronic acids with γ,γ-difluoroallylic acetates has been described. The method allows the synthesis of a variety of gem-difluoroallylated arenes with a tosyloxy group on the C=C double bond, thus providing a good opportunity for down-stream transformations. [ABSTRACT FROM AUTHOR]

An efficient palladium-catalyzed Heck-type reaction of fluoroalkyl halides, including perfluoroalkyl bromides, trifluoromethyl iodides, and difluoroalkyl bromides, has been developed. The reaction proceeds under mild reaction conditions with high efficiency and broad substrate scope, and provides a general and straightforward access to fluoroalkylated alkenes which are of interest in life and material sciences. [ABSTRACT FROM AUTHOR]

gem-Difluoropropargyl bromides are versatile intermediates in organic synthesis, but have rarely been employed in transition-metal-catalyzed cross-coupling reactions. The first palladium-catalyzed gem-difluoropropargylation of organoboron reagents with gem-difluoropropargyl bromides is now reported. The reaction proceeds under mild reaction conditions with high regioselectivity; it features a broad substrate scope and excellent functional-group compatibility and thus provides an attractive approach for the synthesis of complex fluorinated molecules, in particular for drug discovery and development. [ABSTRACT FROM AUTHOR]

Fluorinated olefin-containing benzothiadiazoles have important applications in optoelectronic materials. Herein, we reported the direct olefination of fluorinated benzothiadiazoles, as catalyzed by palladium. The reaction proceeds under mild reaction conditions and shows high functional-group compatibility. A preliminary study of the properties of the resulting symmetrical and unsymmetrical olefin-containing fluorinated benzothiadiazoles in red-light-emitting dyes has also been conducted. [ABSTRACT FROM AUTHOR]

The palladium-catalyzed difluoroalkylation of aryl boronic acids with bromodifluoromethylphosphonate, bromodifluoroacetate, and further derivatives has been developed. This method provides a facile and useful access to a series of functionalized difluoromethylated arenes (ArCF2PO(OEt)2, ArCF2CO2Et, and ArCF2CONR1R2) that have important applications in drug discovery and development. Preliminary mechanistic studies reveal that a single electron transfer (SET) pathway may be involved in the catalytic cycle. [ABSTRACT FROM AUTHOR]

Abstract A palladium catalyzed cross-coupling of fluorinated benzothiadiazoles (FBTs) with allyl chlorides is reported. The significant feature of this method is synthetic simplicity, providing a straightforward access to unsymmetrical and symmetrical alkylated FBT derivatives that are of interest in organic electronic and optoelectronic materials. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract: The first example of Pd-catalyzed aerobic direct olefination of polyfluoroarenes has been developed. The reaction makes use of molecular O2 as terminal oxidant, and provides a cost-efficient and environmentally benign access to polyfluoroarene–alkene structures that are of interest in life and material sciences. [Copyright &y& Elsevier]

An abstract of the article "Palladium-Catalyzed Difluoroalkylation of Aryl Boronic Acids: A New Method for the Synthesis of Aryldifluoromethylated Phosphonates and Carboxylic Acid Derivatives" by Zhang Feng, Qiao-Qiao Min, Yu-Lan Xiao, Bo Zhang, and Xingang Zhang is presented.