| Aromatic amines are important intermediates used for the syntheses of medicines and dyes. Their application, however, will be greatly limited because of their mutagenicity on DNA of creatures. For example, benzidine and @-naphthalene amine, actually though its importance for the syntheses of dyes, especially azo dyes, have been banned for the sake of their strong carcinogenic activities to cause professional bladder cancer. As a result, researchers all over the dye industry have recently become more and more interested in looking for some nonmutagenic aromatic amines, especially the substitutes for benzidine and @-naphthalene amine. Six amino intermediates containing 5,10-dihydrophenophosphazine ring system were prepared on the chance of substituting benzidine or @-naphthalene amine, of which four nonmutagenic amino compounds were converted to 35 azo dyes whose visible spectra and the performances of dyeing on wool, silk and cotton were studied. The results showed that these four amino derivatives of 5,10-dihydrophenophosphazine were potential replacements for benzidine and @-naphthalene amine moiety of certain known genotoxic azo dyes.The forming mechanism of dihydrophenophosphazine by the interaction of Ph2NH and PCl3 was studied, and the possible forming mechanism of spiro phosphonium chloride in the same reaction system was also proposed. It was especially found that 5,10-dihydrophenophosphazine 10-oxide existed the tautomeric equilibrium between "enol" and "ketone" by studying some reaction system on it. The spiro phosphonium chloride can be dissolved in HOAc, but not in alkali media and can not be oxidized by peracetic acid. Such characteristics can make the traditional "two-step" synthetic technique of 10-hyroxy-5,10-dihydrophenophos-phazine 10-oxide be converted to an "one-step" technique, and in this new technique, the yield (40%~50%) of target molecule was increased by 20%~25%, the consumption of raw materials was clearly decreased, reaction time was one day rather than over three days showed in literature, and the technique can readily be repeated. The structure of the target molecule was also identified by surveying its melting point, IR, NMR and Mass spectra.The product obtained from the interaction of (5-methyl-)10-hydroxy-5,10-di-hydrophenophosphazine 10-oxide and SOCl2 was refluxed with RONa in ROH to give five corresponding esters phosphinic acid, viz., 10-methoxy-5,10-dihydro-phenophosphazine 10-oxide, 10-ethoxy-5,10-dihydrophenophosphazine 10-oxide, 10-propoxy-5,10-dihydrophenophosphazine 10-oxide, 10-methoxy-5-methyl-5,10-di-hydrophenophosphazine 10-oxide, and 10-ethoxy-5-methyl-5,l 0-dihydrophenophosphazine 10-oxide. All these compounds have double melting points but 10-methoxy-5,10-dihydrohenophosphazine 10-oxide. When substituting MeOH for MeONa on above technology, however, the methyl ester phosphinic acid with double melting points was also obtained, and its crystal phase was clearly different from its counterpart with single melting point. It was especially noted that the esters derived from 5-methyl phosphinic acid exhibited exothermic phenomena while melting at second temperature.The dark green bis-anion obtained from treatment of 10-hydroxy-5,l0-dihydrophenophosphazine 10-oxide with NaH reacted with Mel at about 120# in anhydrous DMF to give W-methyl phosphinic acid. However, the similar N-methylation of the methyl ester phosphinate was not to give the expected product but to give N-methyl phosphinic acid. It was found that the green N-anion obtained from the methyl ester phosphinate shifted its methyl group from oxygen to nitrogen at the same reaction conditions, and the reaction would be carried out in a special inter-molecular more possibly than in an intramolecular substitution.When nitrating the methyl derivatives of 5,10-dihydrophenophosphazine, the consumption of nitrating reagent was the most important factor influencing the nitration. In the case of the unchanged reaction time and temperature, and the reaction media, when a 9-11-fold excess of HNOs was used...
|
PDF Full Text Request