In this paper we show that simple tris(pyrazolyl)methane (Tpm) ligands can
be equilibrated with substituted pyrazoles to form new 'mixed' tris(pyrazol
yl)methanes. The product ratio depends on the nature of the starting tris(p
yrazolyl)methane, the nature of the substituted pyrazole, and the relative
amounts of these two reagents. The method has been used to easily synthesiz
e several new asymmetric and functionalized Tpm ligands. (C) 2000 Elsevier
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