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Abstract: A highly efficient copper‐mediated aromatic pentafluoroethylation method using TMSCF3 as the sole fluoroalkyl source is described. The reaction proceeds by a key C1 to C2 process, that is, the generation of CuCF3 from TMSCF3, followed by a subsequent spontaneous transformation into CuC2F5. Various aryl iodides were pentafluoroethylated with the TMSCF3‐derived CuC2F5. This method represents the first practical and efficient method for pentafluoroethylation of aryl iodides using commercially available TMSCF3 as a pentafluoroethyl precursor. [ABSTRACT FROM AUTHOR]

Abstract: An unprecedented hypervalent iodine(III) catalyzed Balz–Schiemann reaction is described. In the presence of a hypervalent iodine compound, the fluorination reaction proceeds under mild conditions (25–60 °C), and features a wide substrate scope and good functional‐group compatibility. [ABSTRACT FROM AUTHOR]

A general method for the efficient difluoromethylation of alcohols using commercially available TMSCF2Br (TMS=trimethylsilyl) as a unique and practical difluorocarbene source is developed. This method allows primary, secondary, and even tertiary alkyl difluoromethyl ethers to be synthesized under weakly basic or acidic conditions. The reaction mainly proceeds through the direct interaction between a neutral alcohol and difluorocarbene, which is different from the difluoromethylation of phenols. Moreover, alcohols containing other moieties that are also reactive toward difluorocarbene can be transformed divergently by using TMSCF2Br. This research not only solves the synthetic problem of difluorocarbene-mediated difluoromethylation of alcohols, it also provides new insights into the different reaction mechanisms of alcohol difluoromethylation and phenol difluoromethylation with difluorocarbene species. [ABSTRACT FROM AUTHOR]

A catalytic 1,2-fluorine migration reaction with simple fluoroepoxides at room temperature is reported. Under Brønsted acid catalysis, α-fluorinated ketones are efficiently constructed in the absence of an external fluorine source through a 1,2-fluorine migration reaction. The experimental results indicate that the present 1,2-fluorine migration reaction proceeds via a carbocation intermediate. [ABSTRACT FROM AUTHOR]

Described is a one-pot vicinal fluorination-iodination of arynes at room temperature. The diphenyliodonium salt proved to be a privileged catalyst for this nucleophilic fluorination process using CsF as a fluorine source, and a subsequent facile electrophilic iodination with C4F9I was also found to be crucial to ensure the efficient fluorination. This new synthetic protocol has a broad substrate scope under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Unlike the facile synthesis of β-monofluoromethyl alcohols by nucleophilic monofluoromethylation of epoxides, the synthesis of β-difluoromethyl alcohols by nucleophilic difluoromethylation of epoxides still remains a challenge. Herein, studies on tackling this problem with PhSO(NTBS)CF2H ( 2; TBS= tert-butyldimethylsilyl) are reported. The preorganization of 2 and epoxides with BF3 ⋅Et2O was found to be crucial for the reaction. The reaction shows excellent regioselectivity and has a broad substrate scope. The facile transformation of the ring-opened products to β-difluoromethyl, γ-difluoromethyl, and β-difluoromethylenyl alcohols demonstrates the synthetic utility of the reaction. [ABSTRACT FROM AUTHOR]

Abstract: A facile and highly efficient nucleophilic (phenylthio)difluoromethylation of alkyl halides has been achieved via fluoride ion-mediated substitution reaction using [difluoro(phenylthio)methyl]trimethylsilane (Me3SiCF2SPh). The reaction proceeds well with primary alkyl bromides (or alkyl iodides) in DME solvent when CsF/15-crown-5 was used as the fluoride source/additive. The PhSCF2-containing products can be readily transformed into CF2H-containing compounds via a free-radical desulfurization method. [Copyright &y& Elsevier]

The cover page of the journal "Chinese Journal of Chemistry" is presented.

Abstract: 1,1-Difluoroethysilanes (R3SiCF2CH3, R=Me or Et) were synthesized from 1,1-difluoroethyl phenyl sulfone and chlorosilanes using magnesium metal via reductive 1,1-difluoroethylation. It was confirmed that 1,1-difluoroethylsilanes were effective 1,1-difluoroethylating reagents for carbonyl compounds. [Copyright &y& Elsevier]

Abstract: A hypervalent iodine(III)–CF2SO2Ph compound (3) has been successfully prepared with selective nucleophilic reaction using PhSO2CF2SiMe3 reagent, and this previously unkown compound 3 was found to act as a new electrophilic (phenylsulfonyl)difluoromethylation reagent for a variety of S-nucleophiles under very mild reaction conditions. [Copyright &y& Elsevier]

A novelCu-mediated trifluoromethylthiolation of diazo compoundshas been developed that provides a convenient synthetic route forthe efficient α-trifluoromethylthiolation of simple esters undermild reaction conditions. The reaction is typically carried out atroom temperature, and water could be used to promote the reaction. [ABSTRACT FROM AUTHOR]

Highlights: [•] The reactions between carbonyls and PhSO2CF2H have been accomplished using in situ generated substoichiometric amount of base. [•] A protocol for effective difluoro(phenylsulfonyl)methylation of enolizable aldehydes under basic conditions is developed. [•] The reactivity difference between PhSO2CF2H and CF3H toward carbonyls has been disclosed and rationalized. [ABSTRACT FROM AUTHOR]

Abstract: A series of sulfur-, selenium- and tellurium-containing (phenylchalcogen)difluoromethylation reagents PhSCF2H (1a), PhSeCF2H (1b), and PhTeCF2H (1c) were prepared, and their relative reactivity towards aldehydes, ketones, and imines was investigated. Compared to the former developed (phenylchalcogen)difluoromethylation reagents, these reagents are relatively easily available and more atom-economical in fluoroalkylation reactions. It was found that the efficient nucleophilic (phenylchalcogen)difluoromethylation of aldehydes, ketones, and imines could be achieved with 1a–1c. Reagents 1a and 1b showed better reactivity than 1c toward carbonyl compounds and imines, and PhOCF2H (1d) was found to be unable to undergo similar fluoroalkylation reactions. [Copyright &y& Elsevier]

Abstract: We have investigated the different chlorodifluoromethyl aryl ketones 1a–1g and sulfones 2a–2h as difluorocarbene reagents for O- and N-difluoromethylations. It was found that the sulfone reagents 2 were generally more efficient in difluoromethylation than the ketone reagents 1. Furthermore, while the different substituents on ketone reagents 1 did not show a remarkable impact on the difluoromethylation reaction, the substituent effect on the sulfone reagents 2 was much more significant. Finally, we found that p-chlorophenyl chlorodifluoromethyl sulfone 2d and p-nitrophenyl chlorodifluoromethyl sulfone 2h were among the most powerful difluorocarbene reagents in this category for O-difluoromethylations. [Copyright &y& Elsevier]

Abstract: We have successfully achieved nucleophilic (phenylsulfinyl)difluoromethylation of both enolizable and non-enolizable aldehydes and ketones by using difluoromethyl phenyl sulfone (1) as the fluoroalkylating agent. Although the chemical yields of the reactions are good to excellent, the observed diastereoselectivity is poor (dr=1:1.04–2.03). The present synthetic methodology provides a convenient alternative for the preparation of α-(phenylsulfinyl)difluoromethylated carbinols that were previously synthesized via a two-step procedure. [Copyright &y& Elsevier]

The practical title reaction tolerates various functional groups, including complex steroids. [ABSTRACT FROM AUTHOR]

The article presents chemical equations for article "Nucleophilic Iododifluoromethylation of Carbonyl Compounds Using Difluoromethyl 2-Pyridyl Sulfone" by W. Miao and others published in 2016 issue of journal "Organic Letter."

Efficient reaction conditions are developed for using difluoromethyl-2-pyridyl sulfone as reagent to convert diarylketones (II) as well as aliphatic aldehydes (IV) into the corresponding difluoroolefins (III) and (V). [ABSTRACT FROM AUTHOR]

The reaction differs from the previously known decarboxylative trifluoromethylation protocols as water is involved as a reagent in the reaction. [ABSTRACT FROM AUTHOR]