Coordination of a complete series of N2 reduction intermediates (N2H2, N2H4, and NH3) to an iron phosphine scaffold

Article abstract of DOI:10.1021/ic201873a

The series of dinitrogen reduction intermediates (N₂H ₂, N₂H₄, and NH₃) coordinated to the Fe(DMeOPrPE)₂H⁺(DMeOPrPE = 1,2-[bis(dimethoxypropyl) phosphino]ethane) scaffold has been synthesized or generated. The synthesis of trans-[Fe(DMeOPrPE)₂(NH₃)H][BPh₄] and generation of trans-[Fe(DMeOPrPE)₂(N₂H₄)H] [BPh₄] were achieved by substitu tion of the dinitrogen ligand on trans-[Fe(DMeOPrPE)₂(N₂)H][BPh₄]. The trans-[Fe(DMeOPrPE)₂(N₂H₂)H]⁺ complex and its deprotonated conjugate base, trans-Fe(DMeOPrPE) ₂(N₂H)H, were observed by ³¹P and ¹H NMR from decomposition of trans-[Fe(DMeOPrPE)₂(N₂H ₄)H]⁺ in the presence of excess hydrazine. Attempts to chemically oxidize trans-[Fe(DMeOPrPE)₂(N₂H ₄)H]⁺ to trans-[Fe(DMeOPrPE)₂(N ₂H₂)H][BPh₄] with a variety of oxidizing agents yielded only decomposition products consistent with the intermediate formation of trans-[Fe(DMeOPrPE)₂(N₂H₂)H]⁺ prior to decomposition.