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Abstract In this report, we present the synthesis and structural analysis of CNArMes*2 (ArMes*2 = 2,6-(2,4,6-t-Bu3C6H2)2C6H3). Several unique geometric distortions were observed when compared to other previously reported m-terphenyl isocyanide ligands, which we attribute to intraligand steric clashes resulting from the encumbering tert-butyl groups. Additionally, we provide an executable script (ScanBury) for rapidly producing high-resolution distance-dependent buried volume analysis plots, which allows for a visualization of how geometric distortions effectively reduce the steric encumbrance provided by CNArMes*2. Analysis of a series of bis-m-terphenyl isocyanide iron and nickel complexes highlighted how molecular distortions can further diminish the steric protection provided by larger ligands due to interligand steric clashes. 

The bis-monosubstituted aminocarbene-P₂adduct is a generator of P₂, under the classical triple-bonded form (PP), but it also acts as a bis(phosphinidene) (P–P) synthetic equivalent. 

ABSTRACT The low‐valent 15e⁻monovalent chromium complex, Cp*Cr(CNAr^Dipp2)₂(2) (CNAr^Dipp2= 2,6‐(2,6‐(ⁱPr)₂C₆H₃)₂C₆H₃), was isolated and serves as an isolobal analogue of the unstable, monomeric CpCr(CO)₂fragment. Complex2was found to have an unusual intermediate spin ground state (S= 3/2), which enables reversible N₂binding to afford the 17e⁻low‐spin (S= 1/2) complex, Cp*Cr(N₂)(CNAr^Dipp2)₂(2‐N₂), which is a rare example of an N₂‐induced spin state change. Complex2demonstrates distinct redox activity, which allowed for a stepwise investigation of its N₂binding ability as a function of its redox state. While 1e^–reduction of2or2‐N₂under an N₂atmosphere suppresses N₂dissociation to give a saturated dinitrogen‐bound monoanionic species, KCp*CrN₂(CNAr^Dipp2)₂(4), further reduction leads to complete N₂dissociation to afford the dianionic unsaturated metalloradical, K₂Cp*Cr(CNAr^Dipp2)₂(5). This demonstrates how N₂binding at metal centers is affected by subtle changes to electronic structure, a concept of critical importance to catalytic N₂reduction.