Fe-Catalyzed Three-Component Coupling Reaction of α,β,γ,δ-Unsaturated Carbonyl Compounds and Conjugate Dienes with Alkylsilyl Peroxides and Nucleophiles

Abstract

An Fe­(OTf)2-catalyzed three-component coupling reaction of α,β,γ,δ-unsaturated carbonyl compounds with alkylsilyl peroxides in the presence of certain heteronucleophiles (ROH and indole) is realized under mild reaction conditions. A variety of α,β,γ,δ-diene carbonyl substrates with different substituents were successfully employable via combination with several different alkylsilyl peroxides. This new approach is also applicable to the double functionalization of diene substrates.

Bioinspired Fe(II)‐Mediated Halogenative C−C Bond Activation of Ozonides: Temporary Installment of a Peroxide Bridge Allows Selective C−C Scissions for Replacement of a Carbonyl Group by a Halogen

“…As a result, α-iodoδ-ketoester 2 h-I was obtained in 50% yield (Table 1, entry 18). In the case of FeF 2 , the formation of αfluoro-δ-ketoester 2 h-F was not observed (Table 1, entry 19), suggesting that the Fe salt has to be sufficiently electron rich to open the peroxide. [30] Also, in the case of other halogen sources such as CuBr 2 , CuBr, CuCl and CuI only traces of α-halo-δ-ketoester 2 were observed, and diketone 3 h was formed as the main product (Table 1, entries 20-23).…”

“…From chemical point of view, the possibility of transition metal mediated β-scission of peroxides opens access to ω-functionalized, [15] or unsaturated [16] carboxylic acids, haloketones, [17] and medium-sized and macrolactones. [18] The C-centered radicals formed from peroxides can further react with alkenes, [19] alkynes, [20] in situ generated SO 2 , [21] and diazonium salts [22] to yield functionalized carbonyl compounds (Scheme 1B). Tricyclic monoperoxides can be transformed to 2hydroxy-1,5-diketones.…”

Ferrocenophanium Stability and Catalysis

“…Accordingly, several organic transformations have been reported to be catalyzed by iron-based catalyst systems, such as oxidations, reductions, substitutions, cross-coupling, or polymerization reactions. Iron-based catalysts can range from simple salts like FeX 2 or FeX 3 [ 18 , 19 , 20 ], Fe(OTf) 2 [ 21 , 22 ], Fe(OAc) 2 [ 23 , 24 , 25 , 26 ], or Fe(acac) 3 (acac = acetylacetonato) [ 27 ] to higher-sophisticated metal complexes such as Knölker’s or related complexes [ 28 , 29 ], iron complexes derived from phosphorus- [ 7 , 30 ] or nitrogen-coordinating ligands [ 31 , 32 ] or iron coordination compounds which can catalyze reactions site- or substrate-selectively [ 33 , 34 , 35 ] and enantioselectively [ 36 , 37 , 38 ].…”

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).…”