Catalytic Nitrene Transfer To Alkynes: A Novel and Versatile Route for the Synthesis of Sulfinamides and Isothiazoles

A novel transformation is reported for the reaction of terminal or internal alkynes with the nitrene precursor PhI=NTs (Ts=p-toluenesulfonyl) in the presence of catalytic amounts of Tp(Br3)Cu(NCMe) (Tp(Br3)=hydrotris(3,4,5-tribromo-pyrazolylborate). Two products containing an imine functionality have been isolated from the reaction mixtures, identified as sulfinamides and isothiazoles. The former correspond to the formal reduction of the sulfone group into sulfoxide, whereas the latter involves the insertion of an alkyne carbon atom into the aromatic ring of the N-tosyl moiety.Support for this work was provided by the MINECO (CTQ2014-52769-C3-R-1, CTQ2014-57761-R, Severo Ochoa Excellence Accreditation 2014-2018 SEV-2013-0319, Red Intecat CTQ2014-52974-REDC) and by a FPU fellowship (M.R.R.). We thank Prof. Antonio Echavarren for helpful comments and discussions

Nucleophilic Trifluoromethylation Reactions Involving Copper(I) Species: From Organometallic Insights to Scope

Over the last decades, trifluoromethyl copper(I) complexes have played a key role as reactive species in the formation of C–CF3 bond-forming reactions. This Short Review covers not only select examples of relevant Cumediated or catalyzed nucleophilic trifluoromethylation reactions, one of the most active fields in organic synthesis, but also provides a comprehensive picture of the real behavior of these copper species, including ubiquitous cuprates, in the reaction media

Sustainable knowledge-driven approaches in transition metalcatalyzed transformations

The sustainable synthesis of relevant scaffolds for their use in the pharmaceutical, agrochemical and material sectors constitutes one of the most urgent challenges that the chemical community needs to overcome. In this context, the development of innovative and more efficient catalytic processes based on fundamental understanding of the underlying reaction mechanisms remains a largely unresolved challenge for academic and industrial chemists. Here, we cover selected examples of computational and experimental knowledge-driven approaches for the rational design of transition metal catalyzed transformations

New vistas in transmetalation with discrete “AgCF3” species: Implications in Pd-mediated trifluoromethylation reactions

This work describes the employment of discrete “AgCF3” complexes as efficient transmetalating agents to PdIIto surmount overlooked challenges related to the transmetalation step in Pd- catalyzed trifluoromethylation processes. We report the participation of a unique silver ate (Cs)[Ag(CF3)2] complex, under stoichiometric and catalytic conditions, in the unprecedented one-pot formation of PhCF3 using PhI as starting material. Moreover, we show that the transmetalation step, which is often ignored in these transformations, can also determine the success or failure of the coupling process

Catalytic nitrene transfer yo alkynes: a novel and versatile route for the synthesis of sulfinamides and isothiazoles

A novel transformation is reported for the reaction of terminal or internal alkynes with the nitrene precursor PhI=NTs (Ts=p‐toluenesulfonyl) in the presence of catalytic amounts of TpBr3Cu(NCMe) (TpBr3=hydrotris(3,4,5‐tribromo‐pyrazolylborate). Two products containing an imine functionality have been isolated from the reaction mixtures, identified as sulfinamides and isothiazoles. The former correspond to the formal reduction of the sulfone group into sulfoxide, whereas the latter involves the insertion of an alkyne carbon atom into the aromatic ring of the N‐tosyl moiety.Support for this work was provided by the MINECO (CTQ2014‐52769‐C3‐R‐1, CTQ2014‐57761‐R, Severo Ochoa Excellence Accreditation 2014‐2018 SEV‐2013‐0319, Red Intecat CTQ2014‐52974‐REDC) and by a FPU fellowship (M.R.R.)

Exploring the role of coinage metallates in trifluorometalation: a combined experimental and theoretical study

Despite the known nucleophilic nature of [M(CF3)2]–(M = Cu, Ag, Au), their participation in trifluoromethylation reactions of aryl halides remains unexplored. Herein, we report, for the first time, the selective access to Cu(CF3)2 – species, ubiquitous in Cu-mediated trifluoromethylations, and we rationalize its complex mechanistic scenario and its behavior compared to its silver and gold congeners through a mixture of experimental and computational approaches