Stabilizing P?P: P22–, P2?–, and P20 as bridging ligands

•Redox series with end-on bridging (P2)2?, (P2)??, and (P?P)0 ligands•A P2 complex bonding characteristics comparable to that of free (P?P)0•Stabilizing heavier dipnictogen redox-inactive Lewis acids Chemical synthesis relies on strategies stabilize well-defined molecular building blocks while also retaining their fundamental reactivity. This is illustrated by the classic pnictogen dichotomy. In contrast highly stable N2, higher homologs Pn2 evade isolation—and thus synthetic use—as a result preference p-block elements for ?-bonding. Previous ?-bonded compounds such as coordination electron donors have significantly altered Here, we demonstrate transition-metal fragments strategy under ambient conditions retention P?P triple bond character, in case P2. The release Lewis-acidic capping agents offers transfer reactivity products. work provides new stabilization reactive species multiply bonded heavy use reagents chemical synthesis. its lighter congener neutral diphosphorus observable only gas phase matrix isolation. efforts bases (e.g., carbenes) or led charge electrophilic significant reduction order. report crystallographic, spectroscopic, quantum characterization redox [(?2,?1:?1-P2){Pt(PNP)}2] (PNP = N(CHCHPtBu2)2), which features (P2)2–, (P2)?–, (P2)0 ligands. Although common neutral, triply ligand unprecedented homolog. It was enabled metal gave rise controlled condensed phase. distinct differences between 2p are an intriguing feature periodic table. For example, classical double-bond rule implies instability beyond second period.1Pitzer K.S. Repulsive forces relation energies, distances other properties.J. Am. Chem. Soc. 1948; 70: 2140-2145Crossref Scopus (180) Google Scholar, 2Mulliken R.S. 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