BrCFCN for photocatalytic cyanodifluoromethylation.

Considering the unique electronic properties of the CF and the CN groups, the CFCN group has significant potential in drug and agrochemical development, as well as material sciences. However, incorporating a CFCN group remains a considerable challenge. In this work, we disclose a use of bromodifluoroacetonitrile (BrCFCN), a cost-effective and readily available reagent, as a radical source for cyanodifluoromethylation of alkyl alkenes, aryl alkenes, alkynes, and (hetero)arenes under photocatalytic conditions.

Desulfurization of Thiols for Nucleophilic Substitution.

Although the desulfurization of thiols is a topic of great importance and has received significant attention, most efforts have focused on the hydrodesulfurization of thiols. In this work, we describe the desulfurization of thiols for nucleophilic substitution. This process occurs rapidly, promoted by the PhP/ICHCHI system, and can be extended to a wide range of nucleophiles.

Photocatalytic Keto- and Amino-Trifluoromethylation of Alkenes.

Efforts to develop alternatives to triflic anhydride (TfO) as a trifluoromethylation reagent continue due to its limitations, including volatility, corrosiveness, and moisture sensitivity. Described herein is the use of a trifluoromethylsulfonylpyridinium salt (), easily obtained by a one-step reaction of TfO with 4-dimethylaminopyridine, as a reagent for the trifluoromethylative difunctionalization of alkenes by photoredox catalysis. DMSO and CHCN are suitable solvents for achieving keto- and amino-trifluoromethylation of alkenes, respectively, with good functional group tolerance.

PhP/ICHCHI-promoted reductive deoxygenation of alcohols.

Owing to the ubiquity of the hydroxyl group, reductive deoxygenation of alcohols has become an active research area. The classic Barton-McCombie reaction suffers from a tedious two-step procedure. New efficient methods have been developed, but they have some limitations, such as a narrow substrate scope and the use of moisture-sensitive Lewis acids.

Dehydroxylative Sulfonylation of Alcohols.

Described here is the RP/ICHCHI-promoted dehydroxylative sulfonylation of alcohols with a variety of sulfinates. In contrast to previous dehydroxylative sulfonylation methods, which are usually limited to active alcohols, such as benzyl, allyl, and propargyl alcohols, our protocol can be extended to both active and inactive alcohols (alkyl alcohols). Various sulfonyl groups can be incorporated, such as CFSO and HCFSO, which are fluorinated groups of interest in pharmaceutical chemistry and the installation of which has received increasing attention.

TfO as a CF Source for the Synthesis of Trifluoromethoxylation Reagent CFSOCF.

Described herein is the convenient synthesis of an efficient trifluoromethoxylation reagent, CFSOCF, by using cheap and widely available reagents and without the need of any tedious column chromatography purification procedure.

Difluoromethylsulfonyl Imidazolium Salt for Difluoromethylation of Alkenes.

Herein, we describe the design and synthesis of a difluoromethylsulfonyl imidazolium salt, which can act as a radical difluoromethylation reagent to achieve the challenging amino- and oxy-difluoromethylation of alkenes. Notably, the three steps for the synthesis of the imidazolium salt do not require any tedious distillation or column chromatography purification process, and the amino- and oxy-difluoromethylation paths are simply determined by the selection of reaction solvents.

Synthesis and F Labeling of Alkenyl Sulfonyl Fluorides via an Unconventional Elimination Pathway.

A successful Cu-catalyzed addition of both Cl and SOOCFH groups into alkenes allows us to discover the unusual reactivity of the SOOCFH group. As opposed to common sulfonic esters (RSO-O-R'), in which the R' group is highly electrophilic, the SO moiety demonstrates higher electrophilicity in RSO-OCFH. The unexpected reactivity is further developed not only as a synthetic tool for well-functionalized alkenyl sulfonyl fluorides but also for the first F labeling of alkenyl sulfonyl fluorides.

anti-Markovnikov Iodofluorination of Alkenes.

The fluorination of alkenes with electrophilic N-F type reagents usually occurs through a Markovnikov-type addition, and the anti-Markovnikov-type addition may require the use of a transition metal catalyst or an expensive catalyst. Herein we describe a convenient anti-Markovnikov iodofluorination of alkenes with Selectfluor/ Bu NI. A wide substrate scope and good functional group tolerance were observed.

Starting from Styrene: A Unified Protocol for Hydrotrifluoromethylation of Diversified Alkenes.

In contrast with unactivated alkenes, the corresponding hydrotrifluoromethylation of styrene has remained challenging due to the strong propensity of styrene for oligomerization and polymerization. On the basis of our newly developed trifluoromethylation reagent, TFSP, herein we present a general method for the hydrotrifluoromethylation of styrene under photoredox catalysis. The substrate scope was further extended to unactivated alkenes, acrylates, acrylamides, and vinyl-heteroatom-substituted alkenes.

Transition-metal difluorocarbene complexes.

Although transition metal carbenes have found widespread applications and difluorocarbene has served as a versatile intermediate, it is still quite challenging to make use of transition-metal difluorocarbenes in synthetic chemistry due to their unpredictable reactivities. In this Highlight, we review recent developments in the transition-metal-catalyzed or -mediated transfer of difluorocarbene and the reactivies and conversions of transition-metal difluorocarbene complexes. We start with the MCF bonding, then provide the progress in the transfer of difluorocarbene, and finally briefly discuss the conversions of MCF into other metal complexes.

HCFSe/HCFS Installation by Tandem Substitutions from Alkyl Bromides.

Herein we describe an efficient construction of HCFSe and HCFS groups by tandem substitutions between alkyl bromides and a reagent system consisting of MSeCN (or MSCN) and PhPCFH Br. The tandem process occurs via the first nucleophilic substitution of alkyl bromides by -SeCN (or -SCN) and the subsequent nucleophilic difluoromethylation.

A Readily Available Trifluoromethylation Reagent and Its Difunctionalization of Alkenes.

Trifluoromethyl substitution is notably popular in pharmaceuticals and agrochemicals; however, trifluoromethylated compounds normally rely on the use of cost-prohibitive or gaseous trifluoromethylating reagents, which diminishes the general applicability of these methods. Herein an efficient trifluoromethylation reagent trifluoromethylsulfonyl-pyridinium salt () was reported, which can be readily prepared from cheap and easily available bulk industrial feedstocks. can generate a trifluoromethyl radical under photocatalysis and realize the effective azido- or cyano-trifluoromethylation reactions of alkenes.

Rh-catalyzed tunable defluorinative borylation.

Described herein is a Rh-catalyzed tunable defluorinative borylation of allylic gem-difluorides to provide allylborylated monofluoroalkenes or homoallylborylated monofluoroalkenes with excellent Z/E selectivities. Completely different reaction paths were observed by slightly changing the reaction conditions. Allylborylated monofluoroalkenes were further converted into dihydroxyl-containing monofluoroalkenes.

Difluorocarbene-based cyanodifluoromethylation of alkenes induced by a dual-functional Cu-catalyst.

Although cyanofluoroalkylation has received increasing attention, a toxic cyanation reagent is usually required. Herein, a Cu-catalyzed difluorocarbene-based cyanodifluoromethylation of alkenes with BrCF2CO2Et/NH4HCO3 under photocatalytic conditions is described. BrCF2CO2Et and NH4HCO3 serve as a carbon source and a nitrogen source of the nitrile group, respectively, avoiding the use of a stoichiometric toxic cyanation reagent.

Dehydroxylative Fluorination of Tertiary Alcohols.

A large number of fluorination methods have been developed, but the construction of a tertiary C-F bond remains challenging. Herein, we describe an efficient dehydroxylative fluorination of tertiary alcohols with Selectfluor via the activation of a hydroxyl group by a PhPCHCHPPh/ICHCHI system. Although the reagents appear to be not compatible (Selectfluor with the phosphine and I generated in situ), the reactions occur rapidly to give the desired products in moderate to high yields.

Fluorinated Ylides/Carbenes and Related Intermediates from Phosphonium/Sulfonium Salts.

Owing to the special effects of the fluorine element, including high electronegativity and small atomic radius, the incorporation of a fluorinated group into organic molecules may modify their physical, chemical, and biological properties. Fluorine-containing compounds have found widespread application in a variety of areas, and thus, the development of efficient reagents and methods for the incorporation of fluorinated groups has become a subject of significant interest.Described in this Account are our recent discoveries in the chemistry of fluorinated ylides/carbenes and related intermediates generated from phosphonium/sulfonium salts.

Extraction Behavior of Acidic Phosphorus-Containing Compounds to Some Metal Ions: A Combination Research of Experimental and Theoretical Investigations.

To provide feasible methods for the extraction of valuable metals from spent batteries or low-grade primary ores, the extraction behavior of some representative acidic phosphorus-containing compounds (APCCs) as extractants is evaluated from the perspective of experimental and theoretical investigations in this work. Aqueous solutions containing five metal ions, Ca(II), Co(II), Mg(II), Mn(II), and Ni(II), were made to simulate leaching liquids, and the extraction of these metals was investigated. A simplified calculated model was used to evaluate the interaction between each extractant and metal ions.

A convenient reagent for the conversion of aldoximes into nitriles and isonitriles.

For the dehydroxylation of aldoximes with 4-nitro-1-((trifluoromethyl)sulfonyl)-imidazole (NTSI), slight modifications of reaction conditions resulted in significantly different reaction paths to provide either nitriles or isonitriles. The challenging conversion of aldoximes into isonitriles was achieved under mild conditions.

Oxidation of difluorocarbene and subsequent trifluoromethoxylation.

As a versatile intermediate, difluorocarbene is an electron-deficient transient species, meaning that its oxidation would be challenging. Herein we show that the oxidation of difluorocarbene could occur smoothly to generate carbonyl fluoride. The oxidation process is confirmed by successful trifluoromethoxylation, O-trifluoromethoxylation, the observation of AgOCF species, and DFT calculations.

OsProT1 and OsProT3 Function to Mediate Proline- and γ-aminobutyric acid-specific Transport in Yeast and are Differentially Expressed in Rice (Oryza sativa L.).

Background: Proline (Pro) and γ-aminobutyric acid (GABA) play important roles in plant development and stress tolerance. However, the molecular components responsible for the transport of these molecules in rice remain largely unknown.

Results: Here we identified OsProT1 and OsProT3 as functional transporters for Pro and GABA.

Photocatalyzed Cyanodifluoromethylation of Alkenes.

Difluoromethylation is a straightforward and widely applied strategy used to incorporate HCF into organic molecules. In contrast, cyanation reagents are typically volatile or highly toxic, or they require harsh reaction conditions. Incorporation of both CN and HCF into organic molecules, such as alkenes, is a worthwhile but challenging task.

Difluorocarbene-derived trifluoromethylselenolation of benzyl halides.

Cu-Promoted difluorocarbene-derived trifluoromethylselenolation of benzyl halides with the Ph3P+CF2CO2-/Se/F- system is described. Three new carbon-heteroatom bonds, a Se-CF2 bond, SeCF2-F bond, and C-SeCF3 bond, were sequentially formed in the reaction. This work represents the first trifluoromethylselenolation protocol involving an external fluoride for the generation of the key intermediate, CF3Se- anion.