Precursors hydrazinium

Hydrazinium dications and their related systems can be readily formed and show remarkable stability. These vicinal -dications show enhanced electrophilic reactivities compared to their monocationic precursors. Their chemistry has been recently reviewed,91 therefore only a brief overview is warranted here. Hydrazine itself can be doubly protonated with HC1. When... 

During the decomposition of precursors as mentioned above, additional reactions may occur. With hydrazinium compounds reduction may well take place [40] ... 

It was the latter preparative method and the observation that ReOCl3(PPh3)2 reacts with hydrazinium salts in wet ethanoP to give ReNCl2(PPh3)2 that prompted the development of this synthesis. The precursor complex ReOCl3 (PPhj )2 is perfectly suited for use in this application since it is available conveniently in 10-100-g scales in 99% yield. ... 

The hydrazinium nickel hydrazine carboxylate complex, (N2H5)Ni (N2H3C00)3-H20, is also used as precursor for the synthesis of metallic Ni in the sonochemical preparation of Ni-Mo-S/Al203, since volatile Ni precursors such as Ni(CO)4 are exceptionally toxic and dangerous to use [24]. Similarly, copper hydrazine carboxylate is used to prepare nanoparticles of copper by the sonication method [25]. The presence of a zwitterionic surfactant in the synthesis procedure causes the formation of elongated nanoparticles of aspect ratio 10, which is of significance for electrical applications. In the absence of the zwitterionic surfactant only spherical particles result [26]. 

Hydrazinium mixed metal hydrazine carboxylate complexes of Ni and Co act as a precursor to a bimetallic nano-size powder of Nio.5Coo.5. Overall, it is inferred that metal hydrazine carboxylate derivatives are potential precursors for generating nanocrystalline structures. 

As mentioned in Chapter 1, the development of inorganic derivatives by complex formation with organic anions is of interest from the viewpoint of generating new precursors [7-12]. Several hydrazinium fluorometal-lates have been investigated as their decomposition offers a convenient route for the synthesis of binary fluorides [6]. 

Vanadium compounds have a complex chemistry because of the multiple oxidation states of vanadium. Among these, V2O5 is an important semiconducting material with potential applications as catalysts, chemical sensors, field effect transistors, and electrochemical and photochromism devices. Studies on the reactivity of hydrazinium chloride with NH4VO3 have led to the formation of the ammonium vanadyl complex (NH4)2VO (OH)2Cl2, which is a precursor to the formation of V2O5. 

Catalytic studies of the hydrodesulfurization of thiophene performed at atmospheric pressure in a single-pass microreactor has been studied with Ni-Mo-S/Al203 catalysts derived from the decomposition of (N2H5)Ni (N2H3C00)3 H20 (Figure 6.13). This hydrazinium precursor based catalyst performs better than industrial catalysts [34]. Scanning transmission electron microscopy (STEM) spot analysis shows that Mo is not phase segregated from the promoter metals (Co, Ni, and Co-Ni) on the... 

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