Photoredox/copper-catalyzed -difluoroalkylation-cyanation of 1,3-enynes.

A photoredox/copper-catalyzed 1,4-difunctionalization of 1,3-enynes with readily available difluoroalkylating reagents and TMSCN was developed. This reaction proceeded at mild conditions, affording the corresponding difluoroalkylated allenes in good yields with high functional-group tolerance and excellent regioselectivity.

High-Performance Nonfused Electron Acceptor with Precisely Controlled Side Chain Fluorination.

Modification of the molecular packing of nonfullerene acceptors through fluorination represents one of the most promising strategies to achieve highly efficient organic solar cells (OSCs). In this work, three nonfused electron acceptors, namely, DTCBT-F ( = 0, 5, 9) with precisely controlled amounts of fluorine atoms in the side chains are designed and synthesized, and the effect of side chain fluorination is systematically studied. The results demonstrate that the light absorption, energy levels, molecular ordering, and film morphology could be effectively tuned by precisely controlling the side chain fluorination.

General Synthesis of -Trifluoromethyl Compounds with -Trifluoromethyl Hydroxylamine Reagents.

-CF compounds constitute valuable targets in medicinal chemistry. Extensive studies have been reported for the preparation of -CF compounds through fluorination and trifluoromethylation of N-containing compounds. The development of new synthetic methods from abundant and easily available substrates is highly desirable but still challenging.

Photoredox catalyzed C-H trifluoroethylamination of heteroarenes.

The first C-H trifluoroethylamination of heteroarenes with previously unknown -trifluoroethyl hydroxylamine reagents was achieved under photoredox catalyzed conditions. In the presence of an iridium(III) photoredox catalyst, a variety of heteroarenes, such as indoles, benzofurans, and benzothiophenes, were smoothly converted to the trifluoroethylaminated products in moderate to high yields and with excellent regioselectivity.

Copper-catalyzed chemoselective C-H functionalization of quinoxalin-2(1)-ones with hexafluoroisopropanol.

An unexpected three-component reaction of quinoxalin-2(1H)-ones, tert-butyl peroxybenzoate (TBPB), and hexafluoroisopropanol (HFIP) is described. Under CuBr-catalyzed and TBPB-oxidized conditions, a variety of hydroxyhexafluoroisobutylated quinoxalin-2(1H)-ones were formed. Furthermore, the first hexafluoroisopropoxylation of the quinoxalin-2(1H)-ones with HFIP is also demonstrated with Cu2O as the catalyst and PhI(OAc)2 as the oxidant.

Silver-Catalyzed C-H Aryloxydifluoromethylation and Arylthiodifluoromethylation of Heteroarenes.

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 AgNO and Selectfluor or KSO to give ArOCF- and ArSCF-substituted heteroaromatic compounds in moderate to high yields.

Cascade trifluoromethylthiolation and cyclization of -[(3-aryl)propioloyl]indoles.

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

Bisphenol AF exerts estrogenic activity in MCF-7 cells through activation of Erk and PI3K/Akt signals via GPER signaling pathway.

The negative health effects of bisphenol A (BPA) due to its estrogenic activity result in the increasing usage of alternative bisphenols (BPs) including bisphenol AF (BPAF). To comprehensive understand health effects of BPAF, the MCF-7 cells were used to investigate the effects of BPAF on cell proliferation, intracellular reactive oxygen species (ROS) formation, and calcium ion (Ca) level. The molecular mechanisms of cell biological responses caused by BPAF were investigated by analyzing target protein expression.

Synthesis of CMeCF-Containing Heteroarenes via Tandem 1,1-Dimethyltrifluoroethylation and Cyclization of Isonitriles.

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 CMeCF-containing heteroarenes, which are potentially useful in the drug discovery process.

Transition metal free decarboxylative fluoroalkylation of N-acrylamides with 3,3,3-trifluoro-2,2-dimethylpropanoic acid (TFDMPA).

A novel transition metal-free decarboxylative fluoroalkylation of activated alkenes and C-H functionalization cascade process has been developed. This approach provides an efficient way to construct valuable 1,1-dimethyl-2,2,2-trifluoroethyl substituted oxindoles.

Transition-Metal-Free Decarboxylation of 3,3,3-Trifluoro-2,2-dimethylpropanoic Acid for the Preparation of C(CF)Me-Containing Heteroarenes.

The direct synthesis of C(CF)Me-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(CF)Me-containing heteroarenes were obtained in high yields and have potential applications in the drug discovery process.

Copper-Catalyzed Sulfenylation, Sulfonylation, and Selenylation of 2,3-Allenoic Acids with Disulfides or Diselenides.

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.

Tandem trifluoromethylthiolation/aryl migration of aryl alkynoates to trifluoromethylthiolated alkenes.

A trifluoromethylthiolation initiated aryl migration of aryl alkynoates was disclosed. This protocol employs AgSCF as the SCF 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.

Copper-Assisted Oxidative Trifluoromethylthiolation of 2,3-Allenoic Acids with AgSCF.

The oxidative trifluoromethylthiolation of 2,3-allenoic acids with AgSCF in the presence of (NH)SO 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.

Copper-Catalyzed, Stereoselective Bis-trifluoromethylthiolation of Propiolic Acid Derivatives with AgSCF.

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 AgSCF in the presence of (NH)SO and catalytic Cu(OAc) in MeCN/HCOH afforded bis-trifluoromethylthiolated acrylic acids in moderate to excellent yields with E selectivity. Further derivatization of the resultant products gave a series of polysubstituted SCF-containing alkenes.

Synthesis of Trifluoromethylthiolated Alkenes and Ketones by Decarboxylative Functionalization of Cinnamic Acids.

A tunable decarboxylative trifluoromethylthiolation of cinnamic acids with AgSCF was developed to afford trifluoromethylthiolated alkenes or ketones by using transition metal-mediated conditions.

Iodine-mediated regioselective synthesis of vinyl triflones from styrenes with CF3SO2Na.

An unexpected regioselective synthesis of vinyl triflones was developed. This iodine-mediated C-H triflylation of styrenes with CF3SO2Na occurred at room temperature affording various vinyl triflones, which could be used for the preparation of other CF3SO2-containing compounds.

Synthesis of 3-fluoroalkenyl-3-trifluoromethyl-2-oxindoles by the reaction of indoline-2,3-diones with difluoromethylene phosphabetaine.

An unprecedent reaction of indoline-2,3-diones and (triphenylphosphonio)difluoroacetate (PDFA) afforded novel 3-fluoroalkenyl-3-trifluoromethyl-2-oxindoles in moderate to excellent yields. These products could be transformed into other trifluoromethylated oxindole derivatives.

Anti-crease finishing of cotton fabrics based on crosslinking of cellulose with acryloyl malic acid.

Maleic acid (MA) has been explored to replace formaldehyde-based dimethylol dihydroxy ethylene urea (DMDHEU) for cotton anti-crease finishing. However, the resilience of treated fabrics was not satisfactorily improved. In this study, acryloyl malic acid (AMA) was synthesized and applied on fabrics as a novel crosslinking agent.

Thioether-promoted direct olefination of polyfluoroarenes catalyzed by palladium.

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.

Lewis acid-catalyzed regioselective synthesis of chiral α-fluoroalkyl amines via asymmetric addition of silyl dienolates to fluorinated sulfinylimines.

A tunable and highly regio- and diastereoselective addition of acyclic silyl dienolates 2 to several α-fluoroalkyl sulfinylimines 1 was developed. By appropriate choice of the Lewis acid catalyst, two new chiral α-fluoroalkyl amines 3 and 4 were obtained in good yields and excellent diastereoselectivities (up to >99 : 1 dr), respectively.

Synthesis of γ-monofluorinated goniothalamin analogues via regio- and stereoselective ring-opening hydrofluorination of epoxide.

A stereoselective synthesis of the biologically interesting γ-monofluorinated goniothalamin analogue 2a was described. The features of the synthesis included regioselective reduction of the unprotected hydroxypropynyl moiety of compound 10 by Red-Al, asymmetric Sharpless epoxidation of allyl alcohol 11, and regio- and stereoselective ring-opening hydrofluorination of the hydroxypropynyl epoxide 14 with Et(3)N·3HF in high ee and dr. The chiral hydroxypropynyl fluorohydrin 15 was used as a valuable building block for preparation of a range of γ-monofluorinated α,β-unsaturated δ-lactones.

Nitrogen-rich salts based on energetic nitroaminodiazido[1,3,5]triazine and guanazine.

Highly dense nitrogen-rich ionic compounds are potential high-performance energetic materials for use in military and industrial venues. Guanazinium salts with promising energetic anions and a family of energetic salts based on nitrogen-rich cations and the 6-nitroamino-2,4-diazido[1,3,5]triazine anion (NADAT) were prepared and fully characterized by elemental analysis, IR spectroscopy, (1)H NMR and (13)C NMR spectroscopy, and differential scanning calorimetry (DSC). The crystal structures of neutral NADAT (2) and its biguanidinium salt 5 were determined by single-crystal X-ray diffraction (2: orthorhombic, Pnma; 5: monoclinic, P2(1)).

Taming of the silver FOX.

The first silver-FOX, silver-ammonia-FOX, and silver-amine-FOX compounds were synthesized by the reactions of silver nitrate with K-FOX or guanidine-FOX in water, aqueous ammonia, and amines, respectively. The crystal structure of silver-ammonia-FOX exhibits unique covalent bonding behavior, which is supported by NBO calculations.

Highly dense nitranilates-containing nitrogen-rich cations.

High density energetic salts containing nitrogen-rich cations and the nitranilic anion were readily synthesized in high yield by metathesis reactions of sodium nitranilate 2 and an appropriate halide. All of the new compounds were fully characterized by elemental, spectral (IR, (1)H, (13)C NMR), and thermal (DSC) analyses. The structure of hydrazinium nitranilate (4) was also determined by single-crystal X-ray analysis.