Boron Trifluoride Etherate Research Articles

Fluorination of aromatic compounds with xenon difluoride in the presence of boron trifluoride etherate

Fluorination of benzene with the XeF2—BF3•Et2O system in acetonitrile at low temperatures affords fluorobenzene in 18% yield, the conversion of benzene being 92%. The rest products are di-, tri-, tetra-, and polyphenyls with different fluorination pattern. Toluene and chloro- and bromobenzenes are fluorinated predominantly at the ortho and para positions. Fluorination of 4-nitroanisole affords 2-fluoro-4-nitroanisole in 73% yield.

Synthesis, structure and photoluminescent properties of BF2 and BPh2 complexes with N,O-benzazine ligands

Abstract Novel N,O-bidentate BF2 and BPh2 complexes have been prepared in good to excellent yields through coordination of 8-hydroxy-2-methylquinolines and 2-(2-hydroxyphenyl)-3Н-quinazolin-4-ones with boron trifluoride etherate or triphenylborane under mild conditions. All complexes have been characterized by 1H, 11B and 19F NMR, mass-spectrometry and X-ray crystallography data. Some complexes have been found to exhibit a significant fluorescence in acetonitrile solutions. Electronic and site effects of substituents in both heterocyclic and phenol fragments proved to have a profound impact on quantum yields.

Synthesis of Five-, Six-, and Seven-Membered 1,3- and 1,4-Heterocyclic Compounds via Intramolecular Hydroalkoxylation/Hydrothioalkoxylation of Alkenols/Thioalkenols.

Intramolecular hydroalkoxylation/hydrothioalkoxylation of nitrogen-tethered alkenes and alcohols/thiols mediated by boron trifluoride etherate leads to five-membered thiazolidine, six-membered 1,4-oxazines (morpholines) and tetrahydro-2H-1,4-thiazines (thiomorpholines), and seven-membered 1,4-oxazepanes in good yields.

ChemInform Abstract: Synthesis of Fluorine‐Containing 1,3‐Thiazine Derivatives from Primary Polyfluoroalkanethioamides.

ChemInformVolume 46, Issue 18 Heterocyclic Compounds ChemInform Abstract: Synthesis of Fluorine-Containing 1,3-Thiazine Derivatives from Primary Polyfluoroalkanethioamides. Sergiy S. Mykhaylychenko, Sergiy S. Mykhaylychenko Inst. Org. Chem., Natl. Acad. Sci. Ukr., Kiev 02094, UkraineSearch for more papers by this authorNadiia V. Pikun, Nadiia V. Pikun Inst. Org. Chem., Natl. Acad. Sci. Ukr., Kiev 02094, UkraineSearch for more papers by this authorEduard B. Rusanov, Eduard B. Rusanov Inst. Org. Chem., Natl. Acad. Sci. Ukr., Kiev 02094, UkraineSearch for more papers by this authorYuriy G. Shermolovich, Yuriy G. Shermolovich Inst. Org. Chem., Natl. Acad. Sci. Ukr., Kiev 02094, UkraineSearch for more papers by this author Sergiy S. Mykhaylychenko, Sergiy S. Mykhaylychenko Inst. Org. Chem., Natl. Acad. Sci. Ukr., Kiev 02094, UkraineSearch for more papers by this authorNadiia V. Pikun, Nadiia V. Pikun Inst. Org. Chem., Natl. Acad. Sci. Ukr., Kiev 02094, UkraineSearch for more papers by this authorEduard B. Rusanov, Eduard B. Rusanov Inst. Org. Chem., Natl. Acad. Sci. Ukr., Kiev 02094, UkraineSearch for more papers by this authorYuriy G. Shermolovich, Yuriy G. Shermolovich Inst. Org. Chem., Natl. Acad. Sci. Ukr., Kiev 02094, UkraineSearch for more papers by this author First published: 16 April 2015 https://doi.org/10.1002/chin.201518231Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume46, Issue18May, 2015 RelatedInformation

ChemInform Abstract: BF3 Etherate‐Mediated Microwave‐Assisted Facile Synthesis of Thiopyrano[2,3‐b]indol‐2‐one.

Abstract A facile synthesis of indole annulated 2H-thiopyran-2-ones has been developed by condensation of indoline-2-thiones with acetoacetic esters in the presence of borontrifluoride etherate (BF3 etherate) using microwave irradiation. This one-step operationally simple methodology leads to thiopyrano[2,3-b]indol-2-ones in good yields.

Metal-Free Direct N-Benzylation of Sulfonamides with Benzyl Alcohols by Employing Boron Trifluoride–Diethyl Ether Complex

N-Benzylation of sulfonamides with both primary and secondary benzyl alcohols by employing boron trifluoride–diethyl ether complex under mild reaction conditions has been developed, which is an environmentally benign and facile protocol for assembling a series of primary and secondary benzyl sulfonamides in yields up to 83%. In this coupling reaction, the beneficial role of water has been clarified in detail through control experiments.

Metal-free, one-pot, sequential protocol for transforming α,β-epoxy ketones to β-hydroxy ketones and α-methylene ketones.

A new sequential, one-pot protocol for transforming 1,3-disubstituted 2,3-epoxy ketones to β-hydroxy ketones and α-methylene ketones has been developed. Reaction of epoxy ketones with boron trifluoride etherate (BF3·OEt2) generates the cationic intermediates by regioselective epoxide ring opening and an acyl shift. Then, a treatment of these cations with 2-aryl-1,3-dimethylbenzimidazolines (DMBIH) results in formation of 1,2-disubstituted 3-hydroxy ketones. DMBIH serves as a hydride donor in the second step of this process. Finally, the β-hydroxy ketones can be converted to 1,2-disubstituted 2-methylene ketones by treatment with methanesulfonic acid or a combination of methanesulfonyl chloride and triethylamine. Importantly, the sequential steps involved in formation of the α-methylene ketone products can be carried out in one pot.

Boron-Catalyzed Arylthiooxygenation of N-Allylamides: Synthesis of (Arylsulfanyl)oxazolines

Oxazoles and aryl sulfides are chemical entities that are found in many natural products and biologically and pharmaceutically active molecules. It is therefore highly desirable to develop an efficient and practical approach to the synthesis of arylsulfanyl-substituted oxazolines. We developed a simple and efficient method for boron-catalyzed sequential arylsulfanylation and oxygenation of <i>N</i>-allylamides. The protocol uses readily available 1-(arylsulfanyl)pyrrolidine-2,5-diones as the arylsulfanylation reagents and inexpensive boron trifluoride etherate as the catalyst; no ligands or additives are required, and it is not necessary to purge the reaction vessel of air. The method therefore provides an efficient and practical strategy for the synthesis of arylsulfanyl-substituted heterocycles.

Synthesis of 1,4- and 1,5-Diaryl-1H-Imidazoles

A simple method for the synthesis of 1,4- and 1,5-diarylimidazoles has been developed. The method is based on the condensation of appropriate α-diketone monooxime with aromatic amines and formaldehyde in the presence of boron trifluoride etherate leading to the formation of stable boron trifluoride complexes of imidazole N-oxides. Further reduction of these complexes led to the formation of corresponding imidazoles.

Carbazole Functionalized Star Shaped Triazine Monomer and Its Electrochromic Applications

A new star shape monomer, 2,4,6-tris((9H-carbazol-2-yl)oxy)-1,3,5-triazine (CTR) was synthesized. It was electrochemically polymerized in boron trifluoride diethyl etherate (BFEE)/acetonitrile (ACN) solvent couple. The interaction between BFEE and the CTR lowers the oxidation potential of the monomer and the catalytic effect of BFEE facilitated the formation of high quality polymer film. Electrochemically prepared P(CTR) film was characterized via CV, SEM, FTIR, TGA and UV-vis spectroscopy. Spectroelectrochemical analysis revealed that P(CTR) has high band gap energy which provide it colorless in the neutral state. Electronic transitions of the P(CTR) were observed at 327 and 650 nm, revealing π to π* transitions, and polaron band formation. The polymer switches between dark turquoise and transparent with a switching time of 1.5 s and an optical contrast (%ΔT) of 50%. Electrochromic studies revealed that P(CTR) has opposite properties to EDOT in terms of redox color. In addition to a dual-type complementary colored polymer electrochromic device based on P(CTR) and P(EDOT) was constructed in sandwich configuration. Spectroelectrochemical studies disclosed that the oxidized state of the device shows a blue color and it is transparent in the reduced state. Switching time and maximum contrast (%ΔT) of the device was measured as 3 s and 32% for 615 nm.

Boron trifluoride etherate as a catalyst precursor for coliquefaction of coal and plastics at the mild conditions

The objective of this work is the study of boron trifluoride etherate (C4H10BF3O, a kind of Lewis acid) as a catalyst to depolymerise coal. Coliquefaction of coal and low-density polyethylene (LDPE) using C4H10BF3O with different weight ratio of coal and LDPE were carried out at 370°C. The similar coliquefaction using C4H10BF3O at 200°C, and the similar coliquefaction using ammonium molybdate [(NH4)2MoO4] as catalyst at 370°C were performed for comparison. The result indicates that C4H10BF3O plays a significant role in depolymerisation of coal at 370°C other than 200°C, and oil yield increased approximately 30% when the temperature increased from 200°C to 370°C. The main reason is that coal has a deeper level of cracking at higher temperature. The hexane soluble, hexane insoluble-tetrahydrofuran (THF) soluble and residue organic parts after coliquefaction were analysed by molecular weight, FT-IR, 1H-NMR and 13C-NMR to get confirmatory results. [Received: April 29, 2013; Accepted: November 8, 2013]

Electropolymerization and Electrocatalytic Activity of Poly(4-thienylacetyl-amino-2,2,6,6-tetramethylpiperidinyl-1-yloxy)/(2,2′-bithiophene) Copolymer

Monomer 4-thienylacetyl-amino-2,2,6,6-tetramethylpiperidinyl-1-yloxy (TATEMPO) has been synthesized. The homopolymer poly(2,2′-bithiophene) (PBTh), and poly(4-thienylacetyl-amino-2,2,6,6-tetramethylpiperidinyl-1-yloxy)/(2,2′-bithiophene) (PTATEMPO/BTh) copolymer are successfully prepared on platinum in boron trifluoride diethyl etherate solution by electrochemical polymerization. They are characterized by scanning electron microscopy. The electrochemical copolymerization of TATEMPO and BTh may be accomplished through a radical reaction process. The electrocatalytic oxidation performance of benzyl alcohol in 0.1 M NaClO4-CH3CN solution in the presence of 2,6-lutidine on PTATEMPO/BTh electrode is investigated by cyclic voltammetry and in situ FTIR. Benzyl alcohol is selectively converted to benzaldehyde on the PTATEMPO/BTh electrode, and the overoxidation to benzoic acid is suppressed.

Chemistry of 1,5-diketones: IV. New aspects of the chemistry of 1,5-Dioxo compounds of the 2H-pyran-2-one series

Reactions of 3,3′-(phenylmethanediyl)bis(4-hydroxy-6-methyl-2H-pyran-2-one) with electrophilic (PCl5, CF3COOH, BF3 · Et2O) and nucleophilic reagents (P2S5) in different solvents were studied. The reactions with boron trifluoride-diethyl ether complex in acetic acid and with trifluoroacetic acid gave 4a-hydroxy-3,7-dimethyl-10-phenyl-10,10a-dihydro-1H,4aH,9H-dipyrano[4,3-b: 3′,4′-e]pyran-1,9-dione, while 3,7-dimethyl-10-phenyl-1,9-dioxo-1H,9H-dipyrano[4,3-b: 3′,4′-e]pyran-5-ium tetrafluoroborate was obtained in the reaction with BF3 · Et2O in diethyl ether. Conditions were found for the synthesis of 4-hydroxy-6-methyl-3-[(6-methyl-2-oxo-4-sulfanyl-2H-pyran-3-yl)(phenyl)methyl]-2H-pyran-2-one by reaction of 3,3′-(phenylmethanediyl)bis-(4-hydroxy-6-methyl-2H-pyran-2-one) with diphosphorus pentasulfide.

Synthesis of novel boron chelate complexes and proposed mechanism of new rearrangement

We synthesized novel boron chelate complexes by the reaction of pyrazoline derivatives and boron trifluoride diethyl etherate followed by a new rearrangement. The structures of the compounds were characterized by IR, NMR and HRMS, especially, a typical compound 3c was confirmed by X-ray single crystal analysis. We proposed a mechanism of the rearrangement. Moreover, the absorption and fluorescence spectroscopy of these compounds were measured.

Facile electrochemical polymerization of 2-(thiophen-2-yl)furan and the enhanced capacitance properties of its polymer in acetonitrile electrolyte containing boron trifluoride diethyl etherate

ABSTRACT In this study, a new simple hybrid poly(2-(thiophen-2-yl)furan) (PTFu) was easily electrodeposited by direct anodic oxidation of 2-(thiophen-2-yl)furan in acetonitrile solution containing 0.1 M lithium perchlorate (LiClO 4 ). The oxidation onset potential of 2-(thiophen-2-yl)furan monomer in this medium was measured to be 0.90 V, which was lower than those of thiophene (1.47 V) and furan (1.28 V). The structure and morphology of PTFu were characterized by Ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, and thermal analysis. The electrochemical capacitance properties of PTFu electrode in three electrolytes were also investigated by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscope techniques. The electrochemical results showed that the specific capacitance of PTFu electrode was enhanced to 392.0 F g −1 from 249.4 F g −1 at 5 A g −1 and the cycling stability was also enhanced to 67.0% retention from 25.5% retention after 500 cycles when the equivalent boron trifluoride diethyl etherate (BFEE) was added into the acetonitrile electrolyte. Furthermore, the PTFu electrode in ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (BmimPF 6 ) showed a lower specific capacitance value (209.4 F g −1 at 5 A g −1 ) and an improved stability (67.6% retention after 600 cycles). These results indicated that the conducting polymers based on furan should be a promising electrode material for supercapacitor applications when the electrolyte based-BFEE is used.

ChemInform Abstract: Catalytic Conversion of Aryl Triazenes into Aryl Sulfonamides Using Sulfur Dioxide as the Sulfonyl Source.

AbstractThe first transformation of triazenes into sulfonamides catalyzed by boron trifluoride etherate or copper chloride is described.

Recycling Concept for End-of-Life Silicones: Boron Trifluoride Diethyl Etherate as Depolymerization Reagent to Produce Difluorodimethylsilane as Useful Commodity

The current waste management system is based primarily on landfills, thermal recycling and down-cycling. On the other hand, only a small portion of the end-of-life materials is recycled by depolymerization. In more detail, low-molecular weight commodities/monomers are produced by this process, which can be polymerized in a second step to produce new high quality polymers. Importantly, by applying these depolymerization/polymerization methodologies, contributions to more a sustainable, resource-conserving and environmental-benign society can be made. In this regard, we have set up a capable low-temperature (100 °C) protocol for the depolymerization of poly(dimethylsiloxane)s. In more detail, boron trifluoride diethyl etherate was applied as a depolymerization reagent in the conversion of numerous silicones to obtain difluorodimethylsilane and 1,3-difluoro-1,1,3,3-tetramethyldisiloxane as well-defined products under solvent-free conditions in yields up to 85%. Moreover, it was demonstrated that difluorodime...

Naked-eye and colorimetric detection of arsenic(III) using difluoroboron-curcumin in aqueous and resin bead support systems.

This work presents a new colorimetric method that is simple, rapid and cost effective for the determination of arsenic(III) in water samples. The method is based on changes in the absorbance of difluoroboron-curcumin (BF2-curcumin), prepared by the reaction of borontrifluoride diethyletherate ((C2H5)2OBF3) and curcumin. The BF2-curcumin was dissolved in 60% ethanol, which yielded an orange solution with the maximum absorbance at 509 nm. Upon the addition of arsenic(III), the color of the BF2-curcumin solution changed from orange to blue and the absorbance was measured by UV-visible spectrometry at 632 nm. The BF2-curcumin was applicable in both solution and coated resin. Under the optimal conditions, the detection limits achieved by means of UV-visible spectrometry, naked-eye detection with BF2-curcumin solution and naked-eye detection with BF2-curcumin-coated resin were found to be 0.26, 25 and 30 μM, respectively.

Synthesis of difluoroboron adamantyl-containing complexes and pyrazoles based thereon

One-stage synthesis has been developed for the preparation of adamantyl-containing difluoroboron complexes of 1,3-dicarbonyl compounds from 1-(1-adamantyl)ethanone, boron trifluoride etherate, and carboxylic acids anhydrides. The reaction of the complexes with hydrazine hydrate and its derivatives afforded the corresponding adamantyl-containing pyrazoles.

Synthesis and Properties of Fluorescent Probe for Monosaccharides Based on Exocyclic Ring-Fused Boron Dipyrromethene Dye Substituted with Phenylboronic Ester

2-Ethoxycarbonyl-3,4-tetramethylenepyrrole prepared from cyclohexene through an improved twostep procedure was treated with excess lithium aluminum hydride at high temperature to give 2-methyl-3,4-tetramethylenepyrrole. Further condensation with protected 4-formylphenylboronic acid in the presence of trifluoroacetic acid as catalyst,followed by oxidation with 2,3-dichloro-5,6-dicyanobenzoquinone( DDQ) and treatment with triethylamine and boron trifluoride etherate, gives a novel exocyclic ring-fused borondipyrromethene( BDP) dye derivative substituted with phenylboronic ester subunit at the meso-position. The UV-Vis absorption titration and fluorescence titration measurements for BDP dye derivative were carried out to examine its responsibility to D-fructose,D-galactose,and D-glucose at specific p H. The influence of covalent interactions of BDP dye derivative with monosaccharides on its spectroscopic properties can be selectively recognized by both absorption and fluorescence spectra. By the nonlinear curve-fitting analysis of the fluorescence titration data,the association constants Ksof BDP derivative 1 with monosaccharide such as Dfructose,D-galactose,and D-glucose are 1045,445 and 130 L / mol,respectively. Thus BDP derivative 1 can be used as a sensitive and selective fluorescent probe for monosaccharides. Moreover,the sensing mechanism of the fluorescent probe was also preliminarily discussed.