Kiernicki John J, Shanahan James P, Zeller Matthias, Szymczak Nathaniel K
University of Michigan , 930 N. University , Ann Arbor , MI 48109 , USA . Email:
H. C. Brown Laboratory , Purdue University , 560 Oval Dr , West Lafayette , IN 47907 , USA.
Chem Sci. 2019 May 7;10(21):5539-5545. doi: 10.1039/c9sc00561g. eCollection 2019 Jun 7.
Geometrically flexible 9-borabicyclo[3.3.1]nonyl units within the secondary coordination sphere enable isolation of high-spin Fe(ii)-dihydrides stabilized by boron-hydride interactions and a rare example of an isolable = 3/2 reduction product. The borane-capped Fe(ii)-dihydride: (1) rapidly deprotonates E-H (E = N, O, P, S) bonds to afford borane-stabilized Fe adducts and (2) releases H upon exposure to π-acids. The Lewis acids provide an avenue for redox-leveling in analogy to the near constant operating potential for N reduction in nitrogenase.
二级配位球内具有几何柔性的9-硼双环[3.3.1]壬基单元能够分离出通过硼氢相互作用稳定的高自旋Fe（II）-二氢化物，这是可分离的S = 3/2还原产物的罕见例子。硼烷封端的Fe（II）-二氢化物：（1）能迅速使E-H（E = N、O、P、S）键去质子化，生成硼烷稳定的Fe加合物；（2）在暴露于π酸时会释放出H。与固氮酶中N还原的近乎恒定的操作电位类似，路易斯酸提供了一种氧化还原调平的途径。
