Arylamines derivatives

Many azo dyes, such as tartrazine (Section 4.04.4.1.3), are susceptible to reduction by bacterial reductases in the intestinal flora. Azo reduction is believed to proceed through a hydrazo intermediate that undergoes subsequent reductive cleavage of the nitrogen-nitrogen bond to yield the arylamine derivatives (B-80MI40406). 

Certain nitro PAHs appear to require metabolism of their N-hydroxy arylamine derivatives in order to induce mutations. For example, while 2-nitrofluorene showed decreased mutagenicity in the nitroreductase-deficient mutant, TA98NR, and in strain TA98/1,8-DNP, its presumed ultimate mutagenic derivative, N-hydroxy-2-aminofluorene was inactive in only strain TA98/1,8-DNP (117). Observations such as these led McCoy t al. (117) to... 

The formation of a diazonium group from the arylamine derivative can be done by treatment with sodium nitrite in HC1 (see Protocol in Chapter 9, Section 6). 

Results from an inhalation study showed that a low level (5-10 adducts/10 nucleotides) of arylamine-derived DNA adducts was formed in the olfactory epithelium of female Wistar rats exposed to an average atmospheric concentration of 0.7-2.0 mg/m 4,4 -methylenediphenyl diisocyanate for 17 h per day on five days per week for one year. Adducts were not detected in DNA from lung, liver, bladder, kidney, respiratory epithelium or peripheral blood lymphocytes of exposed animals (Vock et al., 1996). 

T. Yoshioka, H. Yamada, and T. Uematsu, Glycosides of W-hydroxy-V-arylamine derivatives. Part 2. Convenient synthetic methods for W-glycosides of W-hydroxy-V-arylamines, J. Chem. Soc., Perkin Trans. I, (1985) 1271-1276. 

The majority of aniline rearrangements embraces the transformations of the arylamine derivatives bearing various substituents at the nitrogen atom. These substituents can be connected to the nitrogen atom by the N—C or N—heteroatom (N, O, S, Hal) bond. The rearrangements may occur either by migration of the substituent to the aromatic nucleus or by rebuilding of the N-side chain itself. 

Intramolecular oxidative aminations of olefins have alsobeen studied, and many of these intramolecular processes were observed prior to the analogous intermolecular variants. The oxidative aminations of alkenes with arylamines and arylamine derivatives catalyzed by palladium complexes were shown by Hegedus to form indoles (Equation 16.120). These reactions were conducted with orf/io-allylaniline and ort/zo-allylaniline derivatives as substrate, Pd(NCMe)jCl2 as catalyst, and benzoquinone as oxidant. Intramolecular reactions of N-tosylated aliphatic amines were reported by Larock. ° For example, the tosylamide in Equation 16.121 imdergoes cyclization in high yield in the presence of dioxygen with Pd(OAc)j as catalyst in DMSO. A related reaction (Equation 16.122) was reported recently in toluene solvent with added pyridine. ... 

Reaction with diazotized arylamine derivative of porous glass beads... 

To access useful arylamines derivatives, the palladium catalyst is usually prepared as a cationic aqua or diaqua palladium(ll) complex or other organopalladium complex. In the Scheme 6.23, a putative catalytic cycle for the Pd-catalyzed asymmetric addition reaction is shown. The hydroxyl-Pd species (A) is formed in the presence of a base or MS that undergo transmettJlation with an organometallic reagent such as ArM to produce the corresponding aryl palladium complex (B). Insertion of an imine substrate into the Ar-Pd bond, followed by hydrolysis, affords the desired product [29b]. 

The methodology also applied to the silylative cyclization reaction of 2,Af-dialkylamines. Thus the reaction of 2,5-dimethyl-Af-methylaniline with diethylsilane subjected to dehydrogenative coupling and provide hydridosilylaniline. Subsequently, selective silylation of the hydridosilylamine led to the corresponding arylamine derivatives in 91% yield (Scheme 11.8). 

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