Abstract: | The reaction of the organolithium derivative {2, 6‐P(O)(OEt)2]2‐4‐tert‐Bu‐C6H2}Li ( 1 ‐Li) with Ph3C]+PF6]— gave the substituted biphenyl derivative 4‐(C6H5)2CH]‐4′‐tert‐Bu]‐2′, 6′‐P(O)(OEt)2]2‐1, 1′‐biphenyl ( 5 ) which was characterized by 1H, 13C and 31P NMR spectroscopy and single crystal X‐ray analysis. Ab initio MO‐calculations reveal the intramolecular O···C distances in 5 of 2.952(4) and 2.988(5)Å being shorter than the sum of the van der Waals radii of oxygen and carbon to be the result of crystal packing effects. Also reported are the synthesis and structure of the bromine‐substituted derivative {2, 6‐P(O)(OEt)2]2‐4‐tert‐Bu]C6H2}Br ( 9 ) and the structure of the protonated ligand 5‐tert‐Bu‐1, 3‐P(O)(OEt)2]2C6H3 ( 1 ‐H). The structures of 1 ‐H, 5 , and 9 are compared with those of related metal‐substituted derivatives. |