Addition of Hydrazines

Although the addition of hydrazine and its derivatives to acetylenic ketones has been studied in considerable detail, their interaction with hydrazones and mono-alkylhydrazones is less well known. Yandovskii and Klindukhova (74ZOR730) have studied the reaction between hydrazones and alkylhydrazones of aliphatic ketones with dipropynylketones and showed that hydrazones of acetone, methyl-ethylketone, and cyclohexane easily add to one of the triple bonds of dipropynylketone to form 4-methyl-1,1,3-trialkyl-2,3-diaza-l,4-nonadien-7-yn-6-ones (yields... 

The reaction of disubstituted diacetylenes with hydrazine hydrate was reported by Darbinyan et al. (70AKZ640). In the first stage the addition of hydrazine to the terminal carbon atom of the diacetylene system is analogous to that of primary amines to diacetylene (69ZC108 69ZC110). With monosubstituted diacetylenes (R = H), hydrazine adds to the terminal triple bond. This leads to the formation of vinylacetylenic hydrazine 22 which cyclizes to dihydropyrazole 23 subjected to further isomerization to the pyrazole 25. It is possible that hydrazine 22 undergoes hydration to the ketone 24 which can easily be cyclized to the pyrazole 25... 

Pentylenetetrazol (188) is a drug with profound stimulatory activity on the central nervous system. As such, the agent was at one time used in shock therapy for treatment of mental disease. Although it has since been supplanted by safer methods, the agents still occupy an important role in various experimental animal models in pharmacology. Addition of hydrazine to the imino ether (186) obtained from caprolactam affords 187. Treat-... 

Nucleophilic Addition of Hydrazine The Wolff-Kishner Reaction 715... 

The addition of hydrazine (and phenylhydrazine) to these polymers proceeds with the opening of the C=N bonds. If the main chain consists of appropriate fragments, this reaction is followed by the degradation of this chain. 

Forshey, D. R. etal., Explosivstoffe, 1969,17(6), 125-129 Addition of hydrazine strongly sensitises nitromethane and its mixtures with methanol to detonation. 

Bi2S3, Bi2Se3. Bismuth nitrate complexed with triethanolamine or EDTA and thioacetamide, with the addition of hydrazine hydrate, have been... 

A diastereoselective synthesis of bis(3,5)pyrazolophanes was accomplished by sequential inter- and intramolecular cycloadditions of homochiral nitrilimine intermediates . A-Alkyl pyrazolidine-3,5-diones were synthesized in a three-step sequence from dialkyl malonates <00JHC1209>. Methyl acetoacetate was employed as the initial substrate to 3-carboxamido-4-pyrazolecatboxylic acid derivatives <00JHC175>. Vilsmeier type reagent 33 reacted with imines 34 to afford enaminoimine hydrochlorides 35, which were transformed to pyrazoles 36 upon addition of hydrazine <0OJHC13O9>. 

Sugar lactones react readily with hydrazine to give crystalline derivatives useful for isolation and identification (127). Thus, addition of hydrazine to a reaction mixture containing an aldonolactone facilitates isolation of the product. The lactone may be regenerated from the hydrazide by treatment with nitrous acid (128). The phenylhydrazides obtained on treatment of aldonolactones with phenylhydrazine are also useful for characterization (129,130). 

Formation of Nitriles via Addition of Hydrazines to Terminal Alkynes... 

The formation of a ruthenium vinylidene is proposed as the key intermediate in the regioselective addition of hydrazine to terminal alkynes [55]. This reaction, which proceeds via addition of the primary amino group of a 1,1-disubstituted hydrazine followed by deamination, provides an unprecedented access to a variety of aromatic and aliphatic nitriles. The tris(pyrazolyl)borate complex RuCl(Tp)(PPh3)2 gave the best catalytic activity in the absence of any chloride abstractor (Scheme 10.17). 

Scheme 10.17 Nitriles from addition of hydrazine to terminal alkynes.

The addition of hydrazine to diphenylvinylene carbonate 92 quantitatively affords a 1 1 mixture of perhydro-l,3,4-oxadiazin-2-one 93 and 2-oxazolidinone 94 derivatives, both of which are smoothly dehydrated with P2O5 to afford 1,3,4-oxadiazin-2-one 95 and 3-amino-2(3//)-oxazolone 96 (Fig. 5.24), respectively. Addition of primary amines to diphenylvinylene carbonate results in exclusive formation of 3-aIkyl-2(3//)-oxazolones, previously investigated as amino protecting groups in peptide synthesis. 

The Addition of Hydrazine Derivatives to Carbonyl Compounds Hydrazono-de-oxo-bisubstitution... 

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