Characterization of an Intermediate in the Ammonia-Forming Reaction of Fe(DMeOPrPE)2N2 with Acid (DMeOPrPE=1,2-[bis(dimethoxypropyl)phosphino]ethane)

被引：20

作者：

Balesdent, Chantal G. ^{[1
]}

Crossland, Justin L. ^{[1
]}

Regan, Daniel T. ^{[1
]}

Lopez, Coralys T. ^{[1
]}

Tyler, David R. ^{[1
]}

机构：

[1] Univ Oregon, Dept Chem, Eugene, OR 97403 USA

来源：

INORGANIC CHEMISTRY | 2013年 / 52卷 / 24期

基金：

美国国家科学基金会;

关键词：

N-2; REDUCTION; DINITROGEN COMPLEXES; IRON; LIGANDS; MOLYBDENUM; HYDROGENATION; HYDRAZINE; DISPROPORTIONATION; LANTHANIDES; CHEMISTRY;

D O I：

10.1021/ic402081q

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The reactivity of Fe(DMeOPrPE)(2)N-2 with water and acid was explored. (DMeOPrPE is the bidentate phosphine 1,2-[bis(dimethoxypropyl)phosphino]ethane.) The complex reacts with acid to form trans-[Fe(DMeOPrPE)(2)(N-2)H](+) and small amounts of ammonia and hydrazine. When reacted with H2O, cis-Fe-(DMeOPrPE)(2)(H)(2) is formed. To increase the yields of ammonia and hydrazine, we investigated the effect of anion, solvent, and acid addition rate on the yields of ammonia. Of these parameters, only the properties of the anion (i.e., of the acid) had a significant impact on the yields of ammonia. The highest yields of NH3 occurred with the largest/least-coordinating anion (triflate). A short-lived purple intermediate (tau(1/2) < 5 s at 23 degrees C) was observed in the reaction of Fe(DMeOPrPE)(2)N-2 with triflic acid. Because the structure of this purple species could potentially provide valuable insights into the mechanism of ammonia formation, a method was developed for independently synthesizing and stabilizing the complex. Spectroscopic characterization of the purple species identified it as the paramagnetic [((DMeOPrPE)(2)Fe)(2)(mu-N-2)](2+) complex (1). This purple dimer (1) exists in equilibrium with yellow, monomeric, paramagnetic [Fe(DMeOPrPE)(2)N-2](+) (2). The role of 1 in the formation of hydrazine and ammonia was probed by reacting 1 with acid.

引用

页码：14178 / 14187

页数：10

共 47 条

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