Unusual C–H Bond Activation and C(sp³)–C(sp³) Bond Formation at an Fe(II) Bis(amide) Carbene Complex

Abstract

Treatment of (IMes)Fe(NTMS 2 ) 2 with 4 equiv of methanesulfonyl chloride (MsCl = MeSO 2 Cl) resulted in a complex reaction sequence involving substitution of two TMS groups for Ms, followed by the unexpected C(sp 3 )−H bond activation of Ms and subsequent C(sp 3 )−C(sp 3 ) bond formation to generate the bimetallic Fe complex, [IMesH] 2 [Cl 2 Fe(N(TMS)SO 2 (CH 2 ) 2 SO 2 N(TMS)) 2 FeCl 2 ] (1) (IMes = 1,3-bis(2,4,6-trimethylphenyl)-imidazole-2-ylidene; TMS = SiMe 3 ). Extending this C−H activation/C−C bond-forming chemistry to larger alkylsulfonyl chloride chains (i.e., Et and Bu) similarly resulted in C− C coupling, but with decreased chemoselectivity. Detailed mechanistic studies, including using possible intermediate model compounds, were performed in order to elucidate a unifying mechanism for this previously unknown avenue to C(sp 3 )−C(sp 3 ) bond formation.

Redox-Controlled Reactivity at Boron: Parallels to Frustrated Lewis/Radical Pair Chemistry

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Resistive Switching Properties in Memristors for Optoelectronic Synaptic Memristors: Deposition Techniques, Key Performance Parameters, and Applications

“…For all of these promising features, resistive memories have great potential for emerging non-volatile memories as well as for processing memories, letting the fast data access to overcome the von Neumann bottleneck. 87 The RS devices 3a). This increasing trend is even more significant in the number of memristor-related articles illustrated in Figure 3b.…”