Metal‐Free Scission of the NO ⁺ Triple Bond

We report the facile and direct room temperature unimolecular scission of the N≡O⁺ triple bond, one of the strongest known chemical bonds with a bond dissociation energy of 1049 kJ mol^-1. The reaction of NO[Al(OR^F)₄] (R^F = C(CF₃)₃) and PNP^t ^Bu (2,6-bis(di-tert-butylphosphinomethyl)pyridine) in CH₂Cl₂ yields the 1,2,3-diazaphospholo[1,5-a]pyridinium derivative [DAPP^t ^Bu]⁺[Al(OR^F)₄]^- (1), featuring the complete cleavage of the N≡O⁺ bond. At -30°C, the reaction intermediate [PNOP^t ^Bu]⁺[Al(OR^F)₄]^- (2), which contains the novel bridging P═N-O-P⁺ motif, can be isolated. Mechanistic insights were gained through quantum chemical calculations, which elucidated the formation pathways of 1 and 2, while NMR spectroscopic kinetic studies quantified the conversion rate from 2 to 1.