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This work demonstrates the unique features of the never used before Py•BrF3complex in the field of aromatic organic fluorinations. The main disadvantage of the noncomplexed BrF3is the fact that usually, in addition to the desired fluorination, a parallel electrophilic aromatic bromination takes place as well. Use of the Py•BrF3complex reduces this electrophilic bromination, which is observed with most reagents based on fluorine and bromine [BrF]. [ABSTRACT FROM AUTHOR]

A synthesis of a wide range of different aliphatic, aromatic, and heterocyclic N-(trifluoromethyl)amides along with aromatic N-(difluoromethylene)-N-(trifluoromethyl)amine derivatives has been developed. The starting materials are the easily available isothiocyanates, and the fluorinating reagent is the commercially available bromine trifluoride. The reaction is performed under mild conditions, and the fluorinated amides and amines are produced in moderate to high yields. [ABSTRACT FROM AUTHOR]

Abstract: Aldehydes or ketones were reacted with 2-(trimethylsilyl)-1,3-dithiane (1) and the products reduced to the corresponding dithianes using tetrafluoroboric acid and sodium borohydride. These sulfur containing compounds were reacted with bromine trifluoride under mild conditions (1–2min, 0°C) with a net result of replacing the carbonyls'' oxygen with the desired difluoromethyl moiety. [Copyright &y& Elsevier]

A general preparation for aromatic and aliphatic, cyclic as well as linear, symmetric and asymmetric difluoromethylenedioxy derivatives is described. The alcohols were reacted with thiophosgene to give thiocarbonates, which in turn were reacted with BrF3. The fluorination step is complete in seconds with moderate to high yields under mild conditions. [ABSTRACT FROM AUTHOR]

Abstract: Chlorodifluoromethyl ethers are easily obtained from the corresponding alcohols. These ethers, when treated with tributyltin hydride, produce difluoromethyl ethers in high yields. [Copyright &y& Elsevier]

Abstract: A new type of gas chromatograph mass spectrometer (GC–MS) was used for semi-online monitoring of organic chemical reactions for their yield optimization, mechanism elucidation, and for obtaining information on the reaction products identity and purity. It was used with reaction mixtures without prior separation and purification as needed for NMR, thereby saving time and effort. Our unique GC–MS named 5975-SMB Supersonic GC–MS is based on GC interface with the MS with supersonic molecular beams (SMB) and on ionization of the sample molecules during their axial flight through an open electron ionization ion source as vibrationally cold molecules. GC–MS with SMB is demonstrated to significantly extend the range of compounds amenable for analysis, practically always giving molecular ions, enabling effective fast GC–MS analysis, and providing elemental formulas via isotope abundance analysis with unit mass resolution quadrupole MS. In addition, it uniquely provides uniform response to all compounds, a feature, which is vital for the measurement of chemical reaction yields. In this manuscript, four different organic synthetic reactions were studied and are described. Based on the collected data, we were able to better understand how the reaction conditions should be optimized in order to maximize the yields and purity of target products. Consequently, we propose that GC–MS with SMB can serve as a novel tool for the fast optimization of chemical reactions. [Copyright &y& Elsevier]

Abstract: A variety of diazafluorenes and diazafluorenones were oxidized using the HOF·CH3CN complex to form the corresponding N,N′-dioxide derivatives under mild conditions. The products exhibit red-shift absorptions in the UV/visible spectrum relative to the parent compounds. Many such oxidations could not be achieved with any other oxygen-transfer agent. [Copyright &y& Elsevier]