Synthesis and reactivity of a nickel(ii) thioperoxide complex: demonstration of sulfide-mediated N₂O reduction

Abstract

The “masked” terminal nickel sulfide [K(18-crown-6)][LtBuNiII(S)] mediates the reduction of N2O by CO, via the thioperoxide complex [K(18-crown-6)][LtBuNiII(η2-SO)].

Electron transfer within β-diketiminato nickel bromide and cobaltocene redox couples activating CO2

“…A carbonate anion is symmetrically coordinating the nickel centre in a square planar fashion, so that the structure of 3 is rather different as compared to the one of {[L tBu Ni II -CO 3 ]K} 6 , where the K + counterion actively participate in the structure construction and lead to aggregation to a hexanuclear complex. 2,24,25 A similar mononuclear outcome for the reaction of 2 with CO 2 was also proved by ATR-IR spectroscopy (ν CO = 1564 cm −1 ; 13 CO 2 : 1578 cm −1 ) and also in this case no Ni-CO 3 Consequently, carbonate is formed from solutions of both 1 and 2 in contact with CO 2 gas, which is notable as solutions of…”

Probing the electronic and mechanistic roles of the μ4-sulfur atom in a synthetic CuZ model system

“…It should be noted that a mononuclear intermediate in which N 2 O bridges across a terminal nickel-sulde bond has been isolated and crystallographically characterized by Hayton and coworkers. 25,26 The accord between the metrical parameters of the activated N 2 O in our computational model with Hayton's experimental data ( Fig. 2b) Thus, we consider this alternative pathway to be unlikely, but we cannot rule it out denitively.…”

Progress toward the Isolation of Late Metal Terminal Sulfides

“…of S 8 results in formation of the disulfide complex, [K(18-crown-6)][ tBu LNi(η 2 -S 2 )] (42) (Scheme 10). [89] Significantly, this reaction reveals that the sulfide ligand in 32 is not just a strong nucleophile but is also redox active. Curiously, though, 32 was found to be unreactive towards cyclohexene, norbornene, styrene, and phenylacetylene.…”

“…In particular, the trityl by-product 34 decomposes to form ; E = S, 39) (Scheme 10). [89,90] Notably, complex 38 is the first structurally characterized transition metal complex bearing the [SCO 2 ] 2ligand. [91] More remarkably, complex 32 reacts with N 2 O, yielding the first example of a cis-thiohyponitrite complex, [K(18-crown-6)][ tBu LNi(SNNO)] (40) (Scheme 10).…”

“…We have also examined the reactivity of our novel cis-thiohy- , [89] a rare example of a structurally characterized thioperoxide complex. [101][102][103][104] Significantly, addition of excess CO to 47 results in O-atom abstraction and re-formation of the terminal sulfide 32, along with CO 2 .…”