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Trifluoromethylation enabled by photochemistry enriched the toolbox of synthetic chemists, to allow the simple and efficient installation of CF3 groups in organic molecules. Herein, we report a cascade addition/annulation reaction of 2‐isocyanobiphenyls towards the synthesis of 6‐trifluoromethylphenanthridines. It is proposed that this reaction is triggered by the CF3 radical generated from photoexcited 2,3‐butanedione (diacetyl) and sodium triflinate. In contrast to classical aromatic trifluoromethylations, this work does not require any additives and features formation of a C–CF3 bond with concomitant construction of an aromatic scaffold. [ABSTRACT FROM AUTHOR]

We report an efficient oxidative radical desulfur-fragmentation and reconstruction of enol triflates for the synthesis of α-CF3 ketones. Preliminary mechanistic studies disclosed that oxidative fragmentation to release a CF3 radical from the triflyl group of enol triflate and subsequent addition of the CF3 radical to another enol triflate form the desired α-CF3 ketones. This method provides a new approach to α-CF3 ketones, featuring the utilization of catalytic amount of oxidants, broad substrate scope, and potential to control the regioselectivity. [ABSTRACT FROM AUTHOR]

A novel method for the conversion of vinyl triflates into α-trifluoromethylated ketones in the absence of external trifluoromethyl sources is described. This process accomplishes an efficient migration of the trifluoromethyl group of the triflate to the α-position in the ketone through a radical process. The reaction proceeds by the addition of a trifluoromethyl radical to the vinyl triflate and subsequent fragmentation of the trifluoromethane sulfonyl radical. Based on this reaction, a one-pot two-step procedure for the trifluoromethylation of ketones was developed. The method presented herein also allows the transfer of perfluoroalkyl groups from vinyl perfluoroalkanesulfonates, which are readily accessible from alkynes and perfluoroalkanesulfonic acids. [ABSTRACT FROM AUTHOR]

Reported herein is the one-pot synthesis of trifluoromethylated amines at room temperature using the bench-stable (Me4N)SCF3 reagent and AgF. The method is rapid, operationally simple and highly selective. It proceeds via a formal umpolung reaction of the SCF3 with the amine, giving quantitative formation of thiocarbamoyl fluoride intermediates within minutes that can readily be transformed to N-CF3. The mildness and high functional group tolerance render the method highly attractive for the late-stage introduction of trifluoromethyl groups on amines, as demonstrated herein for a range of pharmaceutically relevant drug molecules. [ABSTRACT FROM AUTHOR]

AuI/CuI-co-catalyzed tandem 1,3-acyloxy migration/trifluoromethylation reaction of propargyl esters to give α-trifluoromethyl enones in moderate yields and with excellent stereoselectivity is described. It is proposed that the reaction proceeds through the 1,3-acyloxy migration of the propargyl esters catalyzed by AuI to produce an allenic intermediate, followed by its trifluoromethylation to give the final product. [ABSTRACT FROM AUTHOR]

Highlights: [•] This reaction is high-yielding and wide functional group tolerance. [•] A variety of α-trifluoromethyl aryl ketones can be prepared by this practical method. [•] The reaction is experimentally simple and carried out at room temperature. [Copyright &y& Elsevier]

RBF3K is a chemist's BFF: A metal‐free synthetic route to unprecedented organoboron compounds bearing an α‐trifluoromethyl substituent, employing a variety of trifluoroborate (RBF3K) starting materials, is reported. These substrates represent the first isolated α‐trifluoromethylated alkylboron building blocks, and these reagents lead to a variety of useful bench‐stable, synthetic intermediates. Pin=pinacol. [ABSTRACT FROM AUTHOR]

The conversion of an alcohol-based functional group, into a trifluoromethyl analogue is a desirable transformation. However, few methods are capable of converting O-based electrophiles into trifluoromethanes. The copper-mediated trifluoromethylation of benzylic xanthates using Umemoto's reagent as the source of CF3 to form CCF3 bonds is described. The method is compatible with an array of benzylic xanthates bearing useful functional groups. A preliminary mechanistic investigation suggests that the CCF3 bond forms by reaction of the substrate with in situ generated CuCF3 and CuOTf. Further evidence suggests that the reaction could proceed via a radical cation intermediate. [ABSTRACT FROM AUTHOR]

The article presents a study which examines a radical trifluoromethylation of olefins through applying the Langlois reagent. It notes that unactivated olefins have been used as the starting materials. It states that using an olefin as the synthetic precursor instead of a preformed substrate makes the method advantageous. It mentions that mild reaction conditions, wide functional-group tolerance, and the use of an inexpensive trifluoromethylating agent are the main features of the reaction.

These things are sent to tri us: The introduction of CF3 units into organic molecules is important and requires the development of convenient trifluoromethylating reagents. Here, PhI+CF3, an acyclic electrophilic “CF3+” species, is described, including its in situ generation from TMSCF3, PhI(OAc)2, and KF and its direct applications in sp2 CH trifluoromethylations under mild transition‐metal‐free conditions (see scheme). [ABSTRACT FROM AUTHOR]