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We herein describe a protocol to synthesize trifluoromethylated alkyl boronates from alkenes by the mutual activation of the Togni II and the bis(catecholato)diboron reagents in the absence of any catalyst and additives. This reaction enables synthesizing a series of trifluoromethylated alkyl boronates using unactivated alkenes, including natural products and drug derivatives, in a regioselective manner. Moreover, the synthetic utility of the boronic ester present in the product allows access to a range of trifluoromethyl containing compounds. The radical trapping and gas detection experiments reveal that the more Lewis acidic diboron reagent determines the rapid formation of trifluoromethyl and boron centered radicals. [ABSTRACT FROM AUTHOR]

A general and selective method is developed that allows direct vinylic C−H bond trifluoromethylation of 1,1‐diarylalkenes by a high‐valent copper(III) trifluoromethyl complex, producing biologically active trifluoromethylated alkenes (as well as trifluoromethylated carbocyclic compounds). This fundamental reactivity of Cu(III)−CF3 compounds has thus far been unknown. The presence of a tertiary amine is crucial to this reaction, acting as both a weak base and a single electron transfer (SET) promoter to abstract the vinylic hydrogen. This method starts from bulk olefins under cost‐effective conditions (without the need for external noble metal photocatalyst or stoichiometric amounts of oxidant), and thus is valuable for practical and sustainable applications. [ABSTRACT FROM AUTHOR]

Disclosed herein is a novel, redox-neutral protocol for the visible-light-induced radical alkynylation of unactivated olefins. The intramolecular migration of an alkynyl group, by cleaving an inert C−C σ bond, is realized for the first time. A wide range of synthetically useful trifluoroethylated linear alkynes are readily obtained under mild reaction conditions. [ABSTRACT FROM AUTHOR]

An efficient copper-catalyzed trifluoromethylation of trisubstituted allylic and homoallylic alcohols with Togni's reagent has been developed. This strategy, accompanied by a double-bond migration, leads to various branched CF3-substituted alcohols by using readily available trisubstituted cyclic/acyclic alcohols as substrates. Moreover, for alcohols in which β-H elimination is prohibited, CF3-containing oxetanes are isolated as the sole product. [ABSTRACT FROM AUTHOR]

The development of multicomponent reactions for indole synthesis is demanding and has hardly been explored. The present study describes the development of a novel multicomponent, cascade approach for indole synthesis. Various substituted indole derivatives were obtained from simple reagents, such as unfunctionalized alkenes, diazonium salts, and sodium triflinate, by using an established straightforward and regioselective method. The method is based on the radical trifluoromethylation of alkenes as an entry into Fischer indole synthesis. Besides indole synthesis, the application of the multicomponent cascade reaction to the synthesis of pyrazoles and pyridazinones is described. [ABSTRACT FROM AUTHOR]

The incorporation of a trifluoromethyl (CF3) group into organic compounds is of great importance in pharmaceutical, agricultural, and materials science. Trifluoromethylation based on radical intermediates, as a valuable alternative transformation using the inexpensive and stable solid sodium trifluoromethanesulfinate (CF3SO2Na; Langlois' reagent), has attracted much attention and has become a hot research field. This review examines recent advances in radical trifluoromethylation reactions with CF3SO2Na as CF3 source. [ABSTRACT FROM AUTHOR]

The trifluoromethyl group has unique functional properties and is widely used not only in organic chemistry, but also in pharmaceutical and agrochemical science. Here we describe trifluoromethylation reactions of indoles and alkenes using Togni's reagent. These reactions provide useful trifluoromethylated organic compounds, including heterocycles, with high efficiency. [ABSTRACT FROM AUTHOR]

Pd-catalyzed cross-coupling of halides with CF3-substituted diazo compounds or N-tosylhydrazones has been explored for the synthesis of CF3-substituted alkenes and 1,3-butadienes. Pd-carbene migratory insertion plays the key role in these transformations. [ABSTRACT FROM AUTHOR]

Metal‐free: The first metal‐free aryltrifluoromethylation of activated alkenes has been developed. With this method, trifluoromethylated isoquinolinediones, spirobicycles, oxindoles, and α‐aryl‐β‐trifluoromethylamides were obtained with high control of the regioselectivity. [ABSTRACT FROM AUTHOR]

Assistance provided: The directing group in the title reaction not only activates the substrates but also allows the stereospecific formation of cis‐trifluoromethylated products. The reaction is operationally simple and tolerates a wide variety of functional groups, thus providing an efficient method for the stereoselective synthesis of β‐CF3‐functionalized acrylamide derivatives. [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]