Hydrazinate precursors

The most important synthesis of pyrazolones involves the condensation of a hydrazine with a P-ketoester such as ethyl acetoacetate. Commercially important pyrazolones carry an aryl substituent at the 1-position, mainly because the hydrazine precursors are prepared from readily available and comparatively inexpensive diazonium salts by reduction. In the first step of the synthesis the hydrazine is condensed with the P-ketoester to give a hydrazone heating with sodium carbonate then effects cyclization to the pyrazolone. In practice the condensation and cyclization reactions are usually done in one pot without isolating the hydrazone intermediate. 

Fluorofunctional Silylamines and -Hydrazines -Precursors of (Si-N) Ring Systems... 

Cobum, M. D., J. Heterocyclic Chem., 1974, 11, 1099-1100 Most of a series of azodinitropyridines and their hydrazine precursors were explosive, with a sensitivity comparable to that of RDX. Individual compounds are 2,2 -Azo-3,5-dinitropyridine, 3238... 

Srinivasan, T. T., Ravindranathan, P., Cross, L. E., Roy, R., Newnham, R., Sankar, S. G. Patil, K. C. (1988). Studies on high density nickel zinc ferrites and its magnetic properties using novel hydrazine precursors. Journal of Applied Physics, 63, 3789-91. 

Hydrazinate precursors have been employed to prepare a variety of oxides [2], Metal-ceramic composites such as Fe/Al Oj have been prepared by the thermal decomposition of complex ammonium oxalate precursors, (NH )3[Al Fe (C204)3 nHj0] [3], Organoaluminium silicate precursors have been employed to prepare alumino-sihcates [4],... 

Manimekalai, R., Sinduja, C.R., and Thrivikraman, K. (2012) Synthesis and characterization of nickel ferrite nanoparticles from 2,4-dichlorophenoxy acetate hydrazinate precursors. International Journal ofNanoScienceand Nanotechnology, 3, 105-110. 

Gawas, U.B., Verenkar, V.M.S., and Mojumdar, S.C. (2012) Nano-crystalline Mno.3Nio.3Zno.4Fe204 obtained by novel fumarato-hydrazinate precursor method. Journal of Thermal Analysis and Calorimetry, 108, 865-870. 

Patil, K.C., Gajapathy, D., and Pai Verneker, V.R. (1982) Low temperature ferrite formation using metal oxalate hydrazinate precursor. Materials Research Bulletin, 17, 29-32. 

Suresh, K., Mahesh, G.V., and Patil, K.C. (1989) Preparation of cobalt doped - -Fe203 and Mn-Zn ferrites by the thermal decomposition of the hydrazine precursors. Journal of Thermal Analysis and Calorimetry, 35, 1137-1143. 

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