A Practical Synthesis of Tris(pyrazolyl)methylaryls
journal contributionposted on 07.12.2007, 00:00 by Brendan J. Liddle, James R. Gardinier
The preparation of three tris(pyrazolyl)toluidines from trifluoromethylaniline reagents is described that likely takes advantage of (quinoidal) resonance-stabilized activation of the C−F bonds. Subsequent transformations lead to two additional (for a total of five new) tris(pyrazolyl)methylaryls. This simple reaction is remarkable because only one other tris(pyrazolyl)methylaryl has been reported previously, because it is usually very difficult to activate fluoroalkane C−F bonds, and because of the potential scope of the reaction.