A 30-Membered Nonanuclear Cobalt(II) Macrocycle Containing Phosphonate-Bridged Trinuclear Subunits

The reaction of Co­(ClO₄)₂·6H₂O with (trichloromethyl)­phosphonic acid and 3,5-dimethyl-1H-pyrazole in a 3:1:6 ratio in the presence of triethylamine afforded [Co₉(3,5-DMPz)₁₂­(3,5-DMPzH)₆­(Cl₃CPO₃)₃]­(toluene)₇ (1). The latter contains three trinuclear (Co₃) subunits which are linked to each other by three bridging phosphonate ligands affording a 30-membered macrocycle. 1 contains an equilateral triangle comprising the phosphorus atoms of the bridging phosphonate groups. In solution, 1 breaks down into the trinuclear subunits as detected by electrospray ionization mass spectrometry.