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In inorganic chemistry, the trispyrazolylborate ligand, abbreviated Tp−, is an anionic tridentate and tripodal ligand. Trispyrazolylborate refers specifically to the anion ()−, but the term trispyrazolylborate refers to derivatives substituted at on the pyrazolyl rings. This family of compounds are sometimes called scorpionate ligands.〔Trofimenko, S., "Scorpionates: genesis, milestones, prognosis", Polyhedron, 2004, 23, 197-203. 〕〔Trofimenko, S., "Recent advances in poly(pyrazolyl)borate (scorpionate) chemistry", Chem. Rev., 1993, 93, 943-80. 〕 ==Tp ligands== As suggested by the resonance structures, the nitrogen centers that are not bonded to boron are basic. These centers bind to three adjacent sites of a metal such that the simple adducts have C3v symmetry. The facial bonding mode is reminiscent of cyclopentadienyl ligands, although the ligand field stabilization energy of Tp− is weaker as indicated by the fact that Fe(Tp)2 is a spin-crossover complex whereas ferrocene is low-spin. The Tp ligands are usually prepared from the reaction of pyrazole with potassium borohydride:〔S. Trofimenko ”Poly(1-Pyrazolyl)Borates, Their Transition-Metal Complexes, and Pyrazaboles” Inorganic Syntheses, 1970, Volume 12, p 99-109. 〕 :KBH4 + 3 C3H3N2H → K() + 3H2 Intermediates include the monopyrazolylborate (()−) and the bispyrazolylborate (()−). KTp (m.p. 188-189 °C) is a colourless solid that soluble in polar solvents. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Trispyrazolylborate」の詳細全文を読む スポンサード リンク
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