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S‐(Trifluoromethyl)benzothioate (TFBT) has been developed as an inexpensive, bench‐stable, and user‐friendly trifluoromethylthiolation reagent, which can be easily synthesized by using KF as the only fluorine source. By using TFBT, trifluoromethylthiolates with various counterions can be readily obtained. The synthetic application of TFBT was demonstrated by trifluoromethylthiolation‐halogenation of arynes, bis(trifluoromethylthiolation)–halogenation of 1,2‐benzdiynes, nucleophilic substitution of alkyl halides, deoxytrifluoromethylthiolation of alcohols, and cross‐coupling with aryl and vinyl boronic acids. [ABSTRACT FROM AUTHOR]

An efficient method for the selective C‐difluoromethylation of carbon acids with the reagent TMSCF2Br has been developed. A variety of structurally diverse sp3‐ and sp‐hybridized carbon nucleophiles, including esters, amides, fluorenes, terminal alkynes, β‐ketoesters, malonates, and other activated C−H nucleophiles, could be efficiently and selectively transformed into the corresponding C‐difluoromethylated products under mild conditions. This protocol is also effective for the late‐stage difluoromethylation of pharmaceutically relevant molecules and can be readily scaled up. Moreover, ambident substrates with more than one reactive site towards difluorocarbene can be difluoromethylated orthogonally using TMSCF2Br. [ABSTRACT FROM AUTHOR]

Fluoroalkylation reaction, featuring the transfer of a fluoroalkyl group to a substrate, is a straightforward and efficient method for the synthesis of organofluorine compounds. In fluoroalkylation reactions, fluorine substitution can dramatically influence the chemical outcome. On the one hand, the chemistry of alkylation with non-fluorinated reagents may not be applicable to fluoroalkylations, so it is necessary to tackle the fluorine effects to achieve efficient fluoroalkylation reactions. On the other hand, fluorine substitution may bring about new reactivities and transformations that cannot be realized in alkylation with non-fluorinated reagents; thus, fluorine substitution can be used to explore new synthetic methods. This tutorial review provides a brief overview of the unique fluorine effects in recently developed nucleophilic, electrophilic, radical, and transition metal-mediated fluoroalkylation reactions by comparing with either their non-fluorinated counterparts or fluorinated counterparts with different numbers of fluorine substituents. [ABSTRACT FROM AUTHOR]

A pentacoordinate bis(difluoromethyl)silicate anion, [Me3Si(CF2H)2]−, is observed for the first time by the activation of Me3SiCF2H with a nucleophilic alkali-metal salt and 18-crown-6. Further study on its reactivity by tuning the countercation effect led to the discovery and development of an efficient, catalytic nucleophilic difluoromethylation of enolizable ketones with Me3SiCF2H by using a combination of CsF and 18-crown-6 as the initiation system. Mechanistic investigations demonstrate that [(18-crown-6)Cs]+[Me3Si(CF2H)2]− is a key intermediate in this catalytic reaction. [ABSTRACT FROM AUTHOR]

Two‐in‐one: Me3SiCF2Br is an efficient difluorocarbene source and is compatible with both neutral and aqueous basic conditions. Bromide‐ion‐initiated [2+1] cycloaddition with alkenes/alkynes and hydroxide ion promoted α‐addition with (thio)phenols, (thio)alcohols, sulfinates, heterocyclic amines, and H‐phosphine oxides give the corresponding gem‐difluorinated compounds with broad functional‐group tolerance. [ABSTRACT FROM AUTHOR]

Front Cover: S-(Trifluoromethyl)Benzothioate (TFBT): A KF-Based Reagent for Nucleophilic Trifluoromethylthiolation (Chem. Eur. J. 13/2022) Keywords: aryne; multifunctionalization; potassium fluoride; S-(trifluoromethyl)benzothioate; trifluoromethylthiolation EN aryne multifunctionalization potassium fluoride S-(trifluoromethyl)benzothioate trifluoromethylthiolation 1 1 1 03/03/22 20220301 NES 220301 B From inorganic fluoride to organic fluoride b : Just as the old Chinese legend that a carp succeed in leaping over the divine gate will become a Chinese dragon. In the presence of 18- I c i -6, KF succeed in reacting with thiophosgene, leaping over obstacles of unstable SCF SB 3 sb anion intermediate, and is being transformed into trifluoromethylthiolation reagent TFBT, which has been used in trifluoromethylthiolation of a variety of substrates including alkynes, halogenated hydrocarbons, alcohols, boronic acids, etc. [Extracted from the article]

The reaction proceeds with excellent stereocontrol at the chiral fluorinated carbon center, which is attributed to a dynamic kinetic resolution of the chiral α-fluoro carbanions. [ABSTRACT FROM AUTHOR]

Interestingly, in contrast to the previously known detrimental effect of an α-fluorine substitution on SN2 reactions, the presented monofluoromethylation is accelerated by the α-fluorine substitution. [ABSTRACT FROM AUTHOR]

This is a highly efficient method for the difluoromethylenation of C-C multiple bonds yielding difluorocyclopropane derivatives or the difluoromethylation of heteroatom nucleophiles. [ABSTRACT FROM AUTHOR]