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

The reaction of Co­(ClO<sub>4</sub>)<sub>2</sub>·6H<sub>2</sub>O with (trichloromethyl)­phosphonic acid and 3,5-dimethyl-1<i>H</i>-pyrazole in a 3:1:6 ratio in the presence of triethylamine afforded [Co<sub>9</sub>(3,5-DMPz)<sub>12</sub>­(3,5-DMPzH)<sub>6</sub>­(Cl<sub>3</sub>CPO<sub>3</sub>)<sub>3</sub>]­(toluene)<sub>7</sub> (<b>1</b>). The latter contains three trinuclear (Co<sub>3</sub>) subunits which are linked to each other by three bridging phosphonate ligands affording a 30-membered macrocycle. <b>1</b> contains an equilateral triangle comprising the phosphorus atoms of the bridging phosphonate groups. In solution, <b>1</b> breaks down into the trinuclear subunits as detected by electrospray ionization mass spectrometry.