Fe-Catalyzed Alkylazidation of α-Trifluoromethylalkenes: An Access to Quaternary Stereocenters Containing CF₃ and N₃ Groups

Abstract

A concise Fe-catalyzed alkylazidation of α-trifluoromethylalkenes via a C−C bond cleavage/radical addition/ azidation cascade is described. This protocol features a broad substrate scope, excellent functional group compatibility, and the ability to be performed on a gram scale, thus offering a practical and step-economic approach to the synthetically useful tertiary αtrifluoromethyl azides.

Copper‐Catalyzed Asymmetric Radical 1,2‐Alkylesterification of 1,3‐Dienes with Cycloalkyl Hydroperoxides and Acids

“…[10] Such reagent classes have been extensively exploited as efficient precursors to generate diverse distally keto-functionalized alkyl radicals via alkoxy radical-mediated CÀ C bond cleavage under transition-metal-catalyzed redox systems. Notably, the groups of Maruoka, Guo, Wang, and others disclosed a wide range of two-component or three-component radical transformations of these reagents, such as alkylation, [11][12][13][14] allylation, [15,16] olefination, [17] (hetero)arylation, [18] alkynylation, [19] borylation, [20] silylation, [21] halogenation, [21] chalcogenation, [22] and C-heteroatom bond-forming reactions [23,24] . In these processes, a carbonyl moiety and one or two new chemical bonds have been installed simultaneously, providing access to differently functionalized long-chain carbonyl compounds (Scheme 1a).…”

Construction of C–P Bonds from Free Cyclobutanone Oximes and Chlorophosphines via Radical–Radical Coupling

“…Cyclobutanone oximes and their derivatives have sparked special attention from chemists due to their versatile reactivity caused by the intrinsic ring strain. , Most investigations are centered on cyclobutanone oximes bearing an activation group, which readily undergoes N–O homolysis and subsequent β-cleavage to generate a γ-cyanoalkyl radical (Figure a). ,, The resultant γ-cyanoalkyl radical enables various new transformations, as demonstrated by the groups of Duan, , Song, Chen, Zhou et al In contrast to the wide use of activated cyclobutanone oximes, nonactivated free cyclobutanone oximes are only sporadically used. Noticeably, an elegant visible-light-driven reaction of free cyclobutanone oximes with phosphines was disclosed by Yang and co-workers for the functionalization of olefins, wherein the phosphine is used as an in situ activator (Figure b).…”

Manganese‐Mediated Electrooxidative Ring‐Opening Azidation of Cyclobutanol Derivatives with TMSN3

“…However, some obvious limitations need to be noticed. A majority of known methods mainly focus on two-step synthetic process, ring-opening halogenation followed by nucleophilic substitution [9] or presynthesis peroxides followed by Cu or Fe-catalyzed ring-opening, [10] which always suffer from drawbacks of lower atom-and step-economic efficiency. Only few examples about direct ring-opening azidation of tertcycloalkanols have been established with the use of stoichiometric chemical oxidants.…”