Nitrogen reactions with amino group

II,D,l,a) that in the 3-amino compound obtained, the label is nearly exclusively present on the nitrogen of the amino group (Cl 96% Br 93%), proving that the aminodechlorination and aminodebromination have taken place according to the Sn(ANRORC) mechanism. Exploring the amino-lysis of 3-iodo-4-phenyl-l,2,4-triazine (109, X = I) in a reverse manner, which means reaction of unlabeled 109 X =1) with N-labeled potassium amide/liquid ammonia, gave as result that the 3-iodo compound reacts 63% according to the Sn(ANRORC) mechanism. The conclusion from all these experiments is that the formation of the 3-amino compound 110 from 109 (X = Cl, Br, I) can be explained as described in Scheme 11.49 for the aminodemethylthiolation. 

By reactions of l,2,3(5-tetramethyl-4,6-di (alkylamino)borazines with several diamines and 4,4 -diisocyanatodiphenylmethane, it was shown that the thermal stability of the bis(alkylamino)borazine depends on the substituents at the exocyclic nitrogens. Reactions with diamines led to polycondensates such as the ones cited above. However, reaction with diisocyanates gave different results depending on the substitution pattern of the exocyclic amino groups 140,141),... 

The recent chemistry of A-aminopyridinium halides is dominated by the reactions of the corresponding pyridinium ylides generated by deprotonation of the amino group. These 1,3-dipoles undergo cycloaddition with dipolarophiles and react with electrophiles at the nitrogen of the amino group. 

In still other cases, the product of reaction of an electrophile with an aminoazole is from electrophilic attack at a ring carbon. This is electrophilic substitution and is the general result of nitration and halogenation (see Section 3.4.1.4). In such cases, reactions at both cyclic nitrogen and an amino group are reversible. 

The Mai Hard reaction involves attack of the nitrogen of the amino group on the carbon atom of the carbonyl, sometimes followed by removal of water to produce the Schiff base (17.) (Figure 7). Detailed coverage of the Maillard reaction is given elsewhere in this volume by Hodges (18), so only a few examples, particularly those with which the author has had some relation-... 

It is known that molecules with amino groups coordinated to a metal center often require elevated temperatures for activation of the hydrogen atom attached to nitrogen (6), whereas molecules with hydroxyl groups coordinated to the metal atom eliminate hydroxyl protons at room temperature or under mild reaction conditions. 

Walczak introduced chiral substituents onto the nitrogen of uracils (64) via reaction with amino acid derivatives (65). This mild method did not lead to epimerization of the chiral center and offered an alternative to alkylation of the uracil nitrogen. An electron-withdrawing group (nitro or cyano) on the uracil ring was necessary for product (66) formation. 

A few 1-aminopyrroles have been described 203, 347 little is known of the effect upon the properties of the primary amino group of linking it to nitrogen. Reaction with nitrous acid replaces the amino group by... 

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