Unsymmetric Tripod Ligands Related To Tris(pyrazol-1-yl)methane

The syntheses of tripodal ligands related to tris(pyrazol-1-yl)methane are described. The synthesis of bis(pyrazol-1-yl)methanone, N-methylimidazole-2-carbaldehyde, bis(pyrazol-1-yl)(pyridin-2-yl)methane and bis(pyrazol-1-yl)(N-methylimidazol-2-yl)methane are documented. The synthetic strategy relies on condensation of bis(pyrazol-1-yl)methanone, (pz)2C=O, with aldehydes, R(H)C=O, to give (pz)2(R)CH and carbon dioxide.