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MXenes are a new family of 2D carbides or nitrides that have attracted attention due to their layered structure, tunable surface groups and high electrical conductivity. Here, we report for the first time that the Ti2CTx MXene catalyses the selective oxidative dehydrogenation of n‐butane to butenes and 1,3‐butadiene. This catalyst showed higher intrinsic activity compared to a commercial TiC and TiO2 samples in terms of C4 olefin formation rate. We propose that the stabilisation of structural vacancies and the change in composition (from a carbide to a mixed phase oxide) in the MXene causes its higher catalytic activity. These vacancies can lead to a higher concentration of unpaired electrons in the MXene‐derived material, enhancing its nucleophilic properties and favouring the production of olefins. [ABSTRACT FROM AUTHOR]

The neutral, homoleptic pyridylphosphininenickel(0) complex [Ni(2-Py-4,6-Ph 2 -PC 5 H 2 ) 2 ] ( 1 ) has been obtained by reaction of the formal Ni(0) source [(IPr)Ni(H 2 C═CHSiMe 3 ) 2 ] with 2 equiv of 2-(2'-pyridyl)-4,6-diphenylphosphinine ( L ). Compound 1 can be oxidized both electrochemically and through the use of ferrocenium salts, to afford the corresponding Ni(I) complexes [ 1 ]BF 4 , [ 1 (THF)]PF 6 , and [ 1 2 ](BAr F 4 ) 2 . The structures of these salts reveal an interesting dependence on the nature of the anion. While [ 1 ]BF 4 and [ 1 (THF)]PF 6 show trigonal-bipyramidal coordination of Ni in the solid state, [ 1 2 ](BAr F 4 ) 2 exists as a dinuclear Ni(I) complex and possesses a bridging phosphinine moiety in a rare μ 2 mode. Reactions of 1 with halobenzenes highlight the noninnocent behavior of the aromatic phosphinine ligand, leading to the formation of oxidized Ni complexes but not to classical oxidative addition products. The reaction of 1 with bromobenzene affords the λ 5 phosphinine 2 and the bipyramidal Ni(I) complex [ 1 ]Br, whereas a more unconventional oxidation product 3 is formed from the reaction of 1 and iodobenzene.