Synthesis of tris(pyrazolyl)methanes of unprecedented complexity and functionality

In this paper we show that simple tris(pyrazolyl)methane (Tpm) ligands can be equilibrated with substituted pyrazoles to form new ‘mixed’ tris(pyrazolyl)methanes. The product ratio depends on the nature of the starting tris(pyrazolyl)methane, the nature of the substituted pyrazole, and the relative amounts of these two reagents. The method has been used to easily synthesize several new asymmetric and functionalized Tpm ligands.