Dataset Information

Low-temperature N2 binding to two-coordinate L2Fe(0) enables reductive trapping of L2FeN2(-) and NH3 generation.

ABSTRACT: The two-coordinate [(CAAC)2Fe] complex [CAAC = cyclic (alkyl)(amino)carbene] binds dinitrogen at low temperature (T<-80?°C). The resulting putative three-coordinate N2 complex, [(CAAC)2Fe(N2)], was trapped by one-electron reduction to its corresponding anion [(CAAC)2FeN2](-) at low temperature. This complex was structurally characterized and features an activated dinitrogen unit which can be silylated at the ?-nitrogen atom. The redox-linked complexes [(CAAC)2Fe(I)][BAr(F)4], [(CAAC)2Fe(0)], and [(CAAC)2Fe(-I)N2](-) were all found to be active for the reduction of dinitrogen to ammonia upon treatment with KC8 and HBAr(F)4?2?Et2O at -95?°C [up to (3.4±1.0)?equivalents of ammonia per Fe center]. The N2 reduction activity is highly temperature dependent, with significant N2 reduction to NH3 only occurring below -78?°C. This reactivity profile tracks with the low temperatures needed for N2 binding and an otherwise unavailable electron-transfer step to generate reactive [(CAAC)2FeN2](-) .

SUBMITTER: Ung G

PROVIDER: S-EPMC4314396 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Low-temperature N2 binding to two-coordinate L2Fe(0) enables reductive trapping of L2FeN2(-) and NH3 generation.

Ung Gaël G Peters Jonas C JC

Angewandte Chemie (International ed. in English) 20141113 2

The two-coordinate [(CAAC)2Fe] complex [CAAC = cyclic (alkyl)(amino)carbene] binds dinitrogen at low temperature (T<-80 °C). The resulting putative three-coordinate N2 complex, [(CAAC)2Fe(N2)], was trapped by one-electron reduction to its corresponding anion [(CAAC)2FeN2](-) at low temperature. This complex was structurally characterized and features an activated dinitrogen unit which can be silylated at the β-nitrogen atom. The redox-linked complexes [(CAAC)2Fe(I)][BAr(F)4], [(CAAC)2Fe(0)], and ...[more]

PMID: 25394570

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Dataset Information

Low-temperature N2 binding to two-coordinate L2Fe(0) enables reductive trapping of L2FeN2(-) and NH3 generation.

Publications

Low-temperature N2 binding to two-coordinate L2Fe(0) enables reductive trapping of L2FeN2(-) and NH3 generation.

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