2‐(Diphenylphosphinoylmethyl)pyrrole–2‐(diphenylphosphinomethyl)pyrrole (0.43/0.57) and tetrachlorido(5‐diphenylphosphinomethyl‐2H‐pyrrole‐κ2N,P)titanium(IV)

The title phosphine oxide–phosphine, 0.43C₁₇H₁₆NOP·0.57C₁₇H₁₆NP, (I)/(II), was obtained as a 0.861 (6):1.139 (6) cocrystallized mixture. Hydrogen bonding between the two constituents leads to the formation of 2:2 solid‐state assemblies. Instead of forming the expected simple N,P‐chelated system via loss of the N‐bound H atom, reaction of 2‐(diphenylphosphinomethyl)pyrrole, (II), with TiCl₄ leads to the formation of the title titanium(IV) complex, [TiCl₄(C₁₇H₁₆NP)], (IV), containing a rearranged neutral ligand in which the N‐bound H atom moves to one of the pyrrole C atoms, giving a partially unsaturated ring.