Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
J Am Chem Soc. 2013 Jan 16;135(2):534-7. doi: 10.1021/ja307714m. Epub 2013 Jan 8.
Tris(phosphine)borane ligated Fe(I) centers featuring N(2)H(4), NH(3), NH(2), and OH ligands are described. Conversion of Fe-NH(2) to Fe-NH(3)(+) by the addition of acid, and subsequent reductive release of NH(3) to generate Fe-N(2), is demonstrated. This sequence models the final steps of proposed Fe-mediated nitrogen fixation pathways. The five-coordinate trigonal bipyramidal complexes described are unusual in that they adopt S = 3/2 ground states and are prepared from a four-coordinate, S = 3/2 trigonal pyramidal precursor.
描述了具有 N(2)H(4)、NH(3)、NH(2)和 OH 配体的三(膦)硼烷配位的 Fe(I)中心。通过添加酸将 Fe-NH(2)转化为 Fe-NH(3)(+)，并随后还原释放 NH(3)生成 Fe-N(2)，证明了这一过程。该序列模拟了所提出的 Fe 介导的固氮途径的最后步骤。所描述的五配位三角双锥配合物不同寻常之处在于它们采用 S = 3/2 基态，并且由四配位、S = 3/2 三角锥形前体制备。
