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A photochemically induced nickel-catalyzed radical cross-coupling of phthalimido trifluoroethanol with aryl bromides to furnish α-aryl-α-trifluoromethyl alcohols is reported. This reaction proceeds via a photoinduced charge transfer of an electron donor-acceptor complex between Hantzsch ester and phthalimido trifluoroethanol, followed by 1,2-hydrogen atom transfer, to generate the α-hydroxytrifluoroethyl radical for the cross-coupling of aryl bromides. No exogenous photocatalysts or stoichiometric metal reductants are required in this mild and operationally simple protocol. Broad substrate compatibility and excellent functional group tolerance are observed.

An iron-catalyzed coupling reaction of difluoroenol silyl ethers and cyclobutanone oxime esters is described. This protocol provides a convenient access to various previously unknown and potentially useful gem-difluoromethylenated ketonitriles inmoderate to good yields. The transformations of resulting products to other fluorinecontaining products is also documented.

The regioselective C–H heptafluoroisopropylation of heteroarenes with heptafluoroisopropyl silver provided convenient access to a wide range of CF(CF3)2-containing heteroarenes.

Pentafluorosulfanyl chloride (SF5 Cl) is the most prevalent reagent for the incorporation of SF5 group into organic compounds. However, the preparation of SF5 Cl often relies on hazardous reagents and specialized apparatus. Herein, we described a safe and practical synthesis of a bench-stable and easy-to-handle solution of SF5 Cl in n-hexane under gas-reagent-free conditions. The synthetic application of SF5 Cl was demonstrated through the unprecedented reaction with diazo compounds. The chemoselective hydro- and chloropentafluorosulfanylations of α-diazo carbonyl compounds were developed in the presence of K3 PO4 or copper catalyst, respectively. These reactions provide a direct and efficient access to various α-pentafluorosulfanyl carbonyl compounds of high value for potential applications.

Reported herein is a direct and efficient route to 1-bromo-1-fluoroalkanes through the reaction of unactivated alkenes with dibromofluoromethane under photoredox catalysis. The key to the success of these addition reactions is the employment of a suitable photoredox catalyst. In particular, hydro- and bromo-bromofluoromethylated products were chemoselectively formed using THF and DMF/H2O as solvents, respectively. Furthermore, the synthetic application of the prepared 1-bromo-1-fluoroalkanes has been demonstrated by their transformation into a variety of fluorine-containing compounds.

A cascade oxidative trifluoromethylthiolation and cyclization of N-[(3-aryl)propioloyl]indoles with AgSCF3 is described. This protocol allows for the synthesis of novel bis(trifluoromethylthiolated) or trifluoromethylthiolated pyrrolo[1,2-a]indol-3-ones in moderate to good yields. Mechanistic investigations indicated that radical processes were probably involved in these transformations.

Catalytic, intermolecular difunctionalization of alkenes represents an efficient and diverse protocol for the buildup of molecular complexity from abundant materials by forging two chemical bonds in a single operation. Despite important progress in this area, transition-metal-catalyzed three-component difunctionalization of unactivated alkenes remains underdeveloped, mainly because of the low reactivity, reduced polarization, and high tendency toward β-hydride elimination of these compounds. In this context, nickel-catalyzed, selective, intermolecular difunctionalization methods that generally proceed via two distinct reaction pathways, migratory insertion of nickel species into alkenes and radical addition to alkenes, have been developed. This short review highlights recent advances in this area.1 Introduction2 Nickel-Catalyzed Three-Component Difunctionalization of Unactivated­ Alkenes via Migratory Insertion Processes3 Nickel-Catalyzed Three-Component Difunctionalization of Unactivated­ Alkenes via Radical Processes4 Conclusions and Perspectives

The reaction of easily available Morita–Baylis–Hillman (MBH) alcohols with AgSCF3 in the presence of n-Bu4NI and KI affords primary allylic SCF3 products in high yields and excellent regioselectivities. This regioselective dehydroxytrifluoromethylthiolation protocol could also be extended to propargylic alcohols for the preparation of the primary propargylic SCF3 products.

A tandem 1,1-dimethyltrifluoroethylation and cyclization of isonitriles with 3,3,3-trifluoro-2,2-dimethylpropanoic acid was developed. This protocol provides the efficient synthesis of a series of previously unknown CMe2CF3-containing heteroarenes, which are potentially useful in the drug discovery process.

The first copper and zinc copromoted trifluoromethylation using trifluoromethanesulfonic anhydride (Tf2O) as a trifluoromethylating reagent has been developed. The reaction of alkenes or alkynes with Tf2O in the presence of CuX2 (X = Br, Cl), Zn powder, and 2,2'-bipyridine affords bromo(chloro)trifluoromethylated products in good yields. CuX2 plays a dual role as the catalyst and halide source, whereas 2,2'-bipyridine acts as both the activation reagent and ligand.

The oxidative C-H aryloxydifluoromethylation and arylthiodifluoromethylation of heteroaromatic compounds through the decarboxylation of easily accessible aryloxydifluoroacetic acids and arylthiodifluoroacetic acids, respectively, are disclosed. These reactions are promoted by the combination of catalytic AgNO3 and Selectfluor or K2S2O8 to give ArOCF2- and ArSCF2-substituted heteroaromatic compounds in moderate to high yields.

Direct dehydroxytrifluoromethylthiolation of enols and electron-deficient phenols with AgSCF3 in the presence of n-Bu4NI and KI is reported, affording a series of vinyl and aryl trifluoromethyl sulfides in moderate to excellent yields. This work represents a rare example of direct functionalization of Csp2−OH bonds.

The direct synthesis of C(CF3)Me2-substituted heteroarenes by decarboxylative 1,1-dimethyltrifluoroethylation of heteroarenes with 3,3,3-trifluoro-2,2-dimethylpropanoic acid is reported. This method does not need the transition-metal catalyst, and the base is crucial for this reaction. A series of previously unknown C(CF3)Me2-containing heteroarenes were obtained in high yields and have potential applications in the drug discovery process.

Oxidant-induced three-component hydro-, bromo-, and chloroheptafluoroisopropylation of unactivated alkenes are disclosed. In these reactions, the CF(CF3)2 radical was generated from the oxidation o...

The efficient copper-catalyzed sulfenylation and selenylation of 2,3-allenoic acids with disulfides or diselenides were developed, respectively. These reactions proceeded through tandem radical addition/intramolecular cyclization processes, affording a series of 4-sulfenylated and 4-selenylated butenolides in moderate to excellent yields. Moreover, 4-sulfonylated butenolides could also be obtained by sulfenylation of 2,3-allenoic acids and subsequent oxidation. Further transformation of the sulfur- and selenium-containing butenolides afforded the corresponding furan derivatives in good yields.

A visible light induced hydrodifluoromethylation of alkenes derived from oxindoles with (difluoromethyl)triphenylphosphonium bromide was developed. This reaction delivers a series of previously unknown difluoromethylated oxindoles containing C CF 2 H quaternary centers in moderate to excellent yields. The resulting CF 2 H-containing oxindoles are potentially useful in drug discovery.

Alkyl halides are of particular interests in the areas of pharmaceutical, agrochemical, and material sciences. Direct C H halogenation has been recognized as the most efficient method for the introduction of halogen atoms into organic molecules. This Digest paper highlighted some of the most recent and significant developments in the visible light-promoted halogenation of aliphatic C H bonds.

Tens of billion metric tons of anthropogenic CO2 discharged from the burning of fossil fuels lead to an enormous environmental and resource burden. It is charming to transform CO2 to desirable, economical chemicals and materials. Poly(propylene carbonate) (PPC) is an emerging CO2-based material. Herein, we report the design, synthesis and characterization of the reactive hot melt polyurethane adhesive (RHMPA) based on PPC polyol. The resultant RHMPAs exhibit good adhesion properties to multiple substrates including plastics (PC, PMMA, ABS) and metals (aluminium, steel), which is comparable to or even better than conventional RHMPAs prepared from petro-based polyol. Furthermore, the PPC-based RHMPAs have tunable mechanical properties, and are thermally stable in the typical working range of bonding process (up to 270 °C). The study is expected to expand the applications of PPC and provide a new type of CO2-based renewable and eco-friendly materials.

A copper-mediated oxidative pentafluoroethylthiolation of aryl boronic acids with TMSC 2 F 5 and S 8 was developed. This reaction provides a new access to various aryl pentafluoroethyl thioethers. The use of 2-fluoropyridine as the ligand and the ability to carry out the reaction at 70 °C are key features of this oxidative coupling reaction.

The oxidative trifluoromethylthiolation of 2,3-allenoic acids with AgSCF3 in the presence of (NH4)2S2O8 and catalytic copper salt was investigated. A series of 4-aryl-2,3-allenoic acids underwent radical trifluoromethylthiolation/intramolecular cyclization to afford β-trifluoromethylthiolated butenolides, which were conveniently transformed into trifluoromethylthiolated furan derivatives. In contrast, 2-monosubstituted 2,3-allenoic acids were converted into the corresponding 3,4-bis(trifluoromethylthio)but-2-enoic-acids under similar reaction conditions.

A convenient, visible light-induced radical difluoromethylation of aryl-, heteroaryl-, and alkylthiols with difluoromethyltriphenylphosphonium triflate was developed to afford various difluoromethyl thioethers in moderate to excellent yields. The key reaction features include the use of a readily available CF2H radical source, mild reaction conditions, and excellent chemoselective thiol-difluoromethylation.

A copper-catalyzed chemo- and stereoselective oxidative bis-trifluoromethylthiolation of propiolic acid derivatives was achieved by using carboxylic acid as the activating group and formic acid as a cosolvent. The reaction of propiolic acid derivatives and AgSCF3 in the presence of (NH4)2S2O8 and catalytic Cu(OAc)2 in MeCN/HCO2H afforded bis-trifluoromethylthiolated acrylic acids in moderate to excellent yields with E selectivity. Further derivatization of the resultant products gave a series of polysubstituted SCF3-containing alkenes.

A mild and efficient copper-catalyzed oxidative trifluoroethoxylation of aryl and heteroaryl boronic acids with CF 3 CH 2 OH has been developed. This protocol tolerates a range of functional groups, allowing access to a variety of aryl and heteroaryl trifluoroethyl ethers.

A silver triflate (AgOTf)-mediated oxidative pentafluoroethylation of alcohols and phenols with nucleophilic (pentafluoroethyl)trimethylsilane (TMSCF2CF3) using selectfluor as oxidant under mild reaction conditions was developed. This oxidative coupling protocol utilizes broadly available substrates and easily handled reagents to afford various pentafluoroethyl ethers in moderate to excellent yields. Furthermore, this method was extended to the oxidative heptafluoropropylation and ethoxycarbonyldifluoromethylation of alcohols and phenols for preparation of the corresponding fluoroalkyl ethers.

The first example of benzylic C—H triflylation was accomplished with pyridine as a directing group. The reaction of various 2-benzylpyridines and (CF3SO2)2O in the presence of NEt3 in CH2Cl2 proceeded smoothly to afford the corresponding benzyl triflones in moderate to high yields.

A new approach toward the synthesis of aryl triflones was achieved by the formal insertion of arynes into C–SO2CF3 bonds. This reaction proceeds through addition of CF3SO2-containing nucleophiles to the in situ generated arynes and subsequent intramolecular rearrangement.

A trifluoromethylthiolation initiated aryl migration of aryl alkynoates was disclosed. This protocol employs AgSCF3 as the SCF3 source and MeCN as both the solvent and the hydrogen source. This provides a new access to trifluoromethylthiolated alkenes from readily available substrates and reagents.

1,2,3,4-Butane tetracarboxylic acid (BTCA) has been considered as one of the most promising crosslinking agent to replace dimethylol dihydroxy ethylene urea (DMDHEU) for anti-wrinkle finishing on cotton fabrics. However, it could cause significant strength loss of the treated fabrics. In this study, a 5-(carbonyloxy succinic)-benzene-1,2,4-tricarboxylic acid (BSTA) was synthesized and applied as an effective crosslinking agent. The results show that fabrics treated with BSTA present the same or even better anti-wrinkle properties as that with BTCA. FTIR was employed to analyze ester bond formation process on cellulose. Finishing conditions such as agent concentration, curing temperature, and bath pH were also discussed to evaluate crosslinking effect of cellulose. BSTA, as a derivative of photo-active conjugated compound, can absorb ultraviolet lights and offer ultraviolet (UV) protective property on treated materials. The treated fabrics showed excellent UV protection performance due to the addition of aromatic conjugated system on fabrics.

5-(Carbonyloxy succinic)-benzene-1,2,4-tricarboxylic acid (BSTA) was synthesized and applied as an effective cross-linking agent for cotton fabrics. In this study, BSTA was analyzed and compared with two other extensively investigated poly(carboxylic acid)s, 1,2,3,4-butanetetracarboxylic acid (BTCA) and 3,3′4,4′- benzophenone tetracarboxylic acid (BPTCA), in cross-linking cellulose. Possessing both aromatic and aliphatic carboxylic acid groups and respective properties, BSTA can cross-link cellulose as efficiently as BTCA without causing significant loss of tensile strength of the products. In addition, BSTA exhibits better hydrophilicity and higher affinity to cellulose than the aromatic acid. BSTA is able to produce anhydride under high temperature but it is not a rate-determining step in the esterification process. The kinetic data of BTCA, BPTCA, and BSTA with cellulose were calculated by measuring the concentrations of the carboxylic acids on the fabric, showing an order of BPTCA< BSTA< BTCA in react...

A practical and efficient radical coupling of easily available arylthiodifluoroacetic acids and ethynylbenziodoxolone (EBX) reagents has been reported. Under transition metal-free conditions, aryl-substituted EBXs were converted to the corresponding ArSCF2-substituted alkynes in moderate to good yields, whereas TIPS-EBX underwent silver-catalyzed decarboxylative conditions to deliver the desired coupling products. The synthetic utility of this protocol was demonstrated through the transformation of resulting product to other ArSCF2-substituted alkynes and alkenes.

A mild and efficient method for the regioselective C H fluoromethylation of heteroaryl N-oxides with (fluoromethyl)triphenylphosphonium iodide is presented. With LiOt-Bu as the base and DMSO as the solvent, this reaction delivers a series of C2-fluoromethylated pyridine and quinoline derivatives in moderate to good yields. This protocol also extends the synthetic applications of (fluoromethyl)triphenylphosphonium iodide.

A transition-metal-free Sandmeyer-type fluorosulfonylation reaction has been achieved by the three-component reaction of arenediazonium tetrafluoroborates, Na2S2O5, and N-fluorobenzenesulfonimide (NFSI). The reaction proceeds through a radical tandem process, affording various arenesulfonyl fluorides in moderate to high yields. This protocol not only provides a complement to the previous fluorosulfonylation reactions, but also extends the applications of Sandmeyer reaction.

A tunable and practical synthesis of electrophilic sulfenylating reagents, thiosulfonates and disulfides, from inexpensive and easily available sulfonyl chlorides, has been developed. By appropriate choice of solvents, the reaction of sulfonyl chlorides and tetrabutylammonium iodide gave the target products in good to excellent yields, respectively. These transformations probably proceed through a reducing–coupling pathway.

A new application of trifluoromethylating reagent, methyl fluorosulfonyldifluoroacetate (FO2SCF2CO2Me, Chen’s reagent), as the carbomethoxydifluoromethylating reagent under visible light photoredox conditions is reported. The visible-light-induced reaction of FO2SCF2CO2Me with unactivated alkenes, styrenes, or heteroarenes affords a variety of carbomethoxydifluoromethylated products.

The reaction of diaryliodonium salts with difluoromethyltriflate in the presence of TBAT and CuTC gave the corresponding trifluoromethylated arenes in moderate yields. Compared to other difluorocarbene-derived trifluoromethylation reactions, the current one proceeded at mild reaction conditions (room temperature) within short reaction time (5 min).

Under visible-light photoredox conditions, difluoromethyltriphenylphosphonium bromide was used as the precursor of the CF2H radical for bromodifluoromethylation of alkenes. The presence of catalytic CuBr2 resulted in the selective formation of the bromodifluoromethylated products.

A new synthetic method of trifluoromethylated phosphonates was developed via electrophilic trifluoromethylation with Togni reagent. A variety of β-keto phosphonates were converted into the corresponding α-trifluoromethyl-β-keto phosphonates in moderate to good yields. This protocol could also be extended to other fluoroalkylation reactions, such as pentafluoroethylation.

Bromodifluoromethylphosphonium bromide was solely used as the precursor of difluorocarbene. Herein, an unprecedented visible-light-induced hydrodifluoromethylation of alkenes with bromodifluoromethylphosphonium bromide using H2O and THF as hydrogen sources for the synthesis of difluoromethylated alkanes is described. This difluoromethylation is characterized by mild reaction conditions, ready availability of reagents, and excellent functional-group tolerance.

A convenient method for the preparation of trifluoromethylated arenes from the reaction of diaryliodonium salts with TMSCF3 in the presence of CuBF4·(MeCN)4 and KF at room temperature within 25 min was developed. This reaction provides a valuable complement to the previously established trifluoromethylation methods.