Hydrazones phenyl

Occurs in coal tar, in various plants and in faeces, being formed by the action of the intestinal bacteria on tryptophan. It can be prepared by the action of acid on the phenyl-hydrazone of pyruvic acid to give indole-2-carboxylate which can be decarboxylated to indole. 

Phenylhydrazine on exposure to light slowly darkens and eventually becomes deep red in colour salts of the base share this property but to a lesser degree, the sulphate and acetate (of the common salts) being most stable to light. Phenylhydrazine is largely used in organic chemistry to characterise aldehydes and ketones as their phenyl-hydrazones (pp. 342, 345), and carbohydrates as their osazones (pp. 136-140). It is readily reduced thus in the process of osazone formation some of the phenylhydrazine is reduced to aniline and ammonia. On the... 

B.P. Alkylldene Dlmedone (I) Dimedone "Anhydride" (M) 2 4-Dinltn>-phenyl-hydnzone Seml- earbazone />-NItro- phenyl- hydrazone Other Derivatives Cd ss... 

Ketone B.P. M.P. 2 4-DlnltrO phenyi-hydrazone Semiear- bazone Benzal Derivative Phenyl- hydrazone />-Nltro- phenyU hydrazone Other Derivatives... 

Dimedone " Anhydride of Dimedone 2 4-Dlnltro-phenyl-hydrazone Semi- carbazone Ozime Phenyl- hydrazone />-Nltro. phenyl- hydrazone... 

The preparation of crystaUine derivatives, including 2 4-dinitro-phenyl hydrazones, semicarbazones, oximes, phenylhydrazones and p-nitrophenylhydrazones can be carried out as described under Aromatic Aldehydes, Section IV, 135. 

Reactions of ketones use acetone reactions (i), (ii), (iii) and (vi) as for aldehydes cycZohexanone oxime (J scale), cycZohexanone phenyl-hydrazone, and acetone semicarbazone (J scale) as in 111,74. ... 

Acyl-, 4-alkoxycarbonyl- and 4-phenylazo-pyrazolin-5-ones present the possibility of a fourth tautomer with an exocyclic double bond and a chelated structure. The molecular structure of (138) has been determined by X-ray crystallography (Table 5). It was shown that the hydroxy group participates in an intramolecular hydrogen bond with the carbonyl oxygen atom of the ethoxycarbonyl group at position 4 (8OCSCII21). On the other hand, the fourth isomer is the most stable in 4-phenylazopyrazolones (139), a chelated phenyl-hydrazone structure. 

The reduction of 2-methyl-1,2,3,4-tetrahydro-y-carboline (92) with zinc and hydrochloric acid in the presence of mercuric chloride gives the indolenine derivative, 2-methyl-l,2,3,4,4a,9b-hexahydro-y-carbo-line (93). A related compound, 4,9b-diethyl-2-methyl-l,2,3,4,4a,9b-hexahydro-y-carboline (96), was obtained by catalytic hydrogenation of 95, which was prepared by Fischer ring closure of the phenyl-hydrazone 94. The stereochemistry of the B/C ring junction in these... 

A number of instances in which application of the Fischer synthesis led to extended 3,4-dihydro-j8-carbolinium derivatives have been recorded. Typical for this approach is the ring closure of the phenyl-hydrazone 123 to the expected tetracyclic product... 

A mechanism, that has been proposed by G. M. Robinson and R. Robinson, consists of three steps. Initially the phenyl hydrazone 1 undergoes a reversible rearrangement to give the reactive ene-hydrazine 3 ... 

Condensation of l,0-phenanthroline-2-carbaldehyde with a series of primary amines produces terimine systems in which the field can be varied in relatively small steps, leading to a continuous spin transition in the [Fe N6]2+ complex of the system obtained from the bulky t-butylimine 68 [107]. Similarly hydrazones may be obtained, the most important of which, in the present context, is the phenyl-hydrazone 69 (phy) [108]. 

Kasianowicz, J., Benz, R. and McLaughlin, S. (1984). The kinetic mechanism by which CCCP (carbonyl cyanide m-chloro-phenyl-hydrazone) transports protons across membranes, J. Membrane Biol., 82, 179-190. 

Figure 21 Examples of aluminum complexes of phenyl hydrazones and amidines.

Liquid chromatography was developed to analyze carbonyl (2,4-dinitro-phenyl) hydrazones with detection by diode array ultraviolet spectroscopy (DA-UV) and by atmospheric pressure negative chemical ionization (APNCI) mass spectrometry [716]. In addition, LC can be combined with electrospray ionization coupled on-line with a photolysis reactor for better detection and confirmation of photo degradation products [717]. 

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