2- cyclohexane phenylhydrazone

In keeping with the thermodynamic stability of the ene-hydrazine, the mono-phenylhydrazone of cyclohexane-1,3-dione 38 provided only one of two possible isomers 39, or at least, one dominant product 39 on indolization. ... 

Reductive cleavage of phenylhydrazones of carbonyl compounds provides a route to amines. The reduction is carried out conveniently in ethanol containing ammonia over palladium-on-carbon. Ammonia is used to minimize formation of secondary amines, derived by addition of the initially formed amine to the starting material (160). Alternatively, a two-phase system of benzene, cyclohexane, toluene, or dioxane and aqueous hydrochloric acid can be used. 

See Oxygen Cyclohexane-1,2-dione bis(phenylhydrazone) See Other a-PHENYLAZO HYDROPEROXIDES... 

However, a base-catalyzed -elimination in the cyclohexane series, for example, of the inosose phenylhydrazone, may either stop on carbon-2 to give an arylazocyclohexene derivative (41) or, as for the inosose 1,3-bis(phenylhydrazone), proceed further leading to a complete aromatiza-tion (42). (An alternative free-radical mechanism that may explain the... 

The possibility of ring closure was expected to depend on molecular geometry. Thus, photolysis of n-propyl azide (7) in cyclohexane produced only the imine (8) in 59% yield, isolated as the 2,4-dinitro-phenylhydrazone (9). Irradiation of phenylethyl azide (10) resulted... 

Allyl-1-formyl-cyclohexan 5,0 g (0,03 mmol) Allyl-(2-subst.-l-alkenyl)-sulfan und 10,8 g (0,05 mmol) Quecksilber(II)-oxid werden 10 Min. auf 190° erhitzt. Es wird vom schwarzen Riickstand abdestilliert Ausbeute 3,7 g (82%) Schmp. (2,4-Dinitro-phenylhydrazon) 153-154°. 

Scheme 5. Formation of cyclohexane-1,2,3-trione l,3-bis(phenylhydrazone) by a free-radical mechanism.235-241...

The polyhydrazones of cyclopentane-l,3-diones and -1,2,3-triones, like their cyclohexane counterparts, are accessible from 1,3-diones. For example, cyclopentane- 1,3-dione yields cyclopentane-1,2,3-trione 3-phenylhydrazone... 

Vicinal tris(phenylhydrazones) of cyclitols, as with 2-oxo-l,3-bis(phenylhydrazones), possess two chelated-ring structures. The NMR spectra of l,2,3-tris(phenylhydrazono)cyclohexane (64), l,2,3-tris(phenylhydrazono)... 

Scheme 11. Chelated structures of cyclohexane- and cyclopentane-1.2.3-trione tris (phenylhydrazones).270 271...

A. J. Fatiadi, The mechanism of formation of tris(phenylhydrazones) on treatment of cyclohexane-1,3-dione with phenylhydrazine, Carbohydr. Res., 25 (1972) 173-186 Chem. Ind. (London), (1973) 38-40. 

Hydroxymethylene-5-methylcyclohexanone in methanol added to aq. Na-acetate, then benzenediazonium chloride soln. prepared from aniline added during 25 min. with stirring 4-methyl cyclohexane-1,2-dione 1-phenylhydrazone. Y 1S%. D. P. 

A soln. of 1-morpholinocyclohexene in methanol containing methylene blue as sensitizer irradiated under Og with a 625 w. Sylvania Sun Gun light source, whereby 1 equivalent O2 is absorbed during 0.5 hr. cyclohexane-1,2-dione. Y 75% as the bis(phenylhydrazone). F. e., also isolation of intermediates, s. H. H. Wasserman and S. Terao, Tetrah. Let. 1975, 1735. 

Suitably functionalized azoderivatives of jS-diketones (ADB or arylhydrazones of j8-diketones, AHBD) (Scheme 2.2b) are also convenient tiydrosoluble species toward water-soluble catalyst precursors in this field and of particular interest are those bearing an acid substituent (carboxylic or sulfonic group) [21], which can operate without requiring the common presence of an added acid promoter. The acidic moiety conceivably has two main roles provides water solubility and acts as the acid promoter. Hence, the complexes [Cu(ADB)(H20)(Me2NCH0)] (Scheme 2.3b) and [ Cu(/u-ADB)(MeOH) 2][ADB = p-COOH substituted (2-hydroxy-phenylhydrazone)pentane-2,4-dione] appear to behave as dual-role catalyst precursors, in acid-free medium, combining, in each molecule, an active copper center and an acid site (TONs and yields up to 163 and 14%, respectively, are achieved for the model oxidation of cyclohexane, in NCMe/aqueous H2O2, at 50 °C) [21],... 

An attempted Fischer-type bis-indolization of cyclohexane-l,3-dione (43 R = H), and (separately) of dimedone (43 R = Me) involved treatment with 2 equiv. each of phenylhydrazone and phosphorus trichloride, in anhydrous benzene. In addition to the expected bis(phenyUiydrazones) (44a), an oxidation product (44b) was also formed. A mechanism is proposed. 

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