Template‐Controlled Formation of an [11]ane‐P2CNHC Macrocyclic Ligand at an Iron(II) Template

Abstract

AbstractComplex [Fe(η5‐C5H5)(η6‐PhMe)]PF6 reacts with 1,2‐bis[bis(2‐fluorophenyl)phosphanyl]benzene (2) in acetonitrile under irradiation for 6 h to give complex [Fe(η5‐C5H5)(2)(CH3CN)]PF6 ([3]PF6). Reaction of [3]PF6 with 1 equiv. of 2‐azidoethyl isocyanide (4) yields complex [Fe(η5‐C5H5)(2)(4)]X ([5]X) (X = Br, PF6). Staudinger reaction with PPh3 at the azido function followed by hydrolysis of the iminophosphorane with HBr yields compound [6]X (X = Br–, PF6 –) with an NH,NH‐stabilized NHC ligand. The facially coordinated NH,NH‐stabilized NHC and the fluorinated diphosphane ligands were linked by N,N′‐deprotonation of the NHC and nucleophilic attack of the nitrogen atoms at two C–F bonds, which gave – after anion exchange with NH4PF6 – complex [1]PF6 bearing the macrocyclic [11]ane‐P2CNHC ligand.