Dinitrobenzenes catalyst effect

A new assumption to be discussed in this section is that the fourth-order kinetics in SatAr by amines in aprotic solvents is due to the formation of the substrate-catalyst molecular complex. Since 1982, Forlani and coworkers149 have advocated a model in which the third order in amine is an effect of the substrate-nucleophile interaction on a rapidly established equilibrium preceding the substitution process, as is shown in Scheme 15 for the reaction of 4-fluoro-2,4-dinitrobenzene (FDNB) with aniline (An), where K measures the equilibrium constant for ... 

Since the dinitro compounds are rather insoluble in water and the diamines are quite soluble, Benner and Stevenson have developed a method involving reduction of a dispersion of dinitro compound in water, effected by very rapid agitation, using noble-metal catalysts. This process can be run continuously by using a series of vessels to carry out the reduction. Similar reductions of w-dinitrobenzene, in water dispersion, using nickel and copper catalysts were also carried out in the laboratories of I. G. Far-benindustrie.2... 

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