Synthesis and characterization of the cyclodiphosphazane embedded macrocycle tetrabromo-resorcin[4]arene-tetrakis(cyclodiphosphazane) and its tetra-rhodium(I) complex.

The synthesis of a cyclodiphosphazane embedded macrocycle, tetrabromo-resorcin[4]arene-tetrakis(cyclodiphosphazane) [(μ-N( t Bu)P) 2 {μ-(C 6 HBr( o -O) 2 - m -CH n Bu)}] 4 (1), and its tetra-rhodium(I) complex [(μ-N( t Bu)P) 2 {μ-(C 6 HBr( o -O) 2 - m -CH n Bu)}Rh(COD)Cl] 4 (2) is described. The resorcin[4]arene backbone adopts a C 4v symmetric crown conformation in 1, which transforms into a C 2v symmetric boat conformation upon complexation with Rh(I) in the tetra-rhodium(I) complex 2, as evidenced by NMR spectroscopy and X-ray diffraction studies.