Rhenium complexes ammonia

Disappointingly, the rhenium complex also was not capable of producing ammonia. Most generally, protonation of dinitrogen complexes led to evolution of the dinitrogen as the gas, often with the production of metal hydrides, a not unexpected result in view of the electron-richness of the metal sites to which dinitrogen was bound. That we were eventually successful was due to a combination of factors, all important in research, as seasoned practitioners will know. These were persistence, preparedness and serendipity. 

Few dinitrogen complexes of chromium are known. Complex 8 decomposes at 20 C with loss of both N2 and PMes. Treatment of complex 9 with acid produces small quantities of ammonia (7%) and hydrazine (1%). Reaction of the polynuclear complex 10 with water regenerates the starting rhenium complex tran5-[ReCl(N2)(PMe2Ph)4], and with dioxygen produces the cation [ReCl(N2)(PMe2Ph)4]. ... 

The rhenium analog can be prepared by a similar route (302 ). However, unlike the manganese complex, (r/ -CsHjlRelCOMl i] readily disproportionates to the dinitrogen and ammonia complexes at room temperature. 

In another example, ammonia molecules coordinated to a rhenium center of a half-sandwich complex, 107, are hydrogen-bonded to 18-crown-6 [434]. 

From the viewpoint of competitive adsorption we can consider as well the sorption of precursors upon the synthesis of Pt-Be/Al203 catalysts from H2PtCl3 and rhenium acid [4] and of Pt-Ru/ 02 catalysts from the ammonia complexes of Pt and Ru [5]. In both cases precursors were in the same ionic form and adsorbed on the same sites. 

The same diamido-complex was prepared by treatment of ReCl3-4NH3 with liquid ammonia. Further heating of [ReCl(NH2)2(NH3)2] resulted in the formation of the imido-complex, [Re2(NH)Cl]n, and, ultimately, rhenium nitride, [Re2N]n- ... 

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