Reaction with aromatic amines

Two investigations on coupling reactions with aromatic amines to yield N- and C-coupling products have been carried out, namely the 7V-couplings with aniline (Beranek and Vecera, 1970) and with 7V-methylaniline (Beranek et al., 1972). ... 

The experimental values of rate constants of R02 reactions with aromatic amines (AmH) are given in Database [52], The experimental measurement of the rate constant /c7 for aromatic amines from kinetics of oxidation faced with great difficulties. These difficulties arise due to the extremely high activity of aminyl radicals toward hydroperoxide [53-56], The reaction... 

According to these parameters, the activation energy of the peroxyl radical reaction with aromatic amine can be calculated using the reaction enthalpy by the equation [54]... 

Kinetic Parameters of Free Radical Reactions with Aromatic Amines in IPM Model [34,54]... 

Reactions with aromatic amines - the HERON reaction... 

Option A involves preparation of triaminotriarylmethane derivatives and their subsequent reaction with aromatic amines in the presence of acidic catalysts. 

Aminobenzoic acid 1.4 g 4-aminobenzoic acid + 3.2 ml 90% orthophosphoric acid in 100 ml methanol Dip Reaction with aromatic amine in hot acid... 

Chlorination of thiobenzyl derivative 494 led to 557, whose reaction with aromatic amines afforded the ZV-aryl-1,2,4-triazolo[l, 5-c]pyrimidine-2-sulfonamide 558 (89EUP343752 93USP5177206). 

N-Heterocyclization.1 1,5-Pentanediol reacts with primary amines at 150-180° in the presence of a ruthenium catalyst to form N-substituted piperidines. For the reaction with aromatic amines RuC I QHs) is the catalyst of choice. On the other hand, the most effective catalyst for the reaction with aliphatic amines is RuC13 combined with either tributylphosphine or triethylphosphine. 

In a preliminary communication Sziman and Messmer reported kinetic deuterium isotope effects in C-coupling reactions of 4-methoxybenzenediazonium tetra-fluoroborate with N,N-dimethylaniline, m-toluidine, 1- and 2-naphthylamine in nitrobenzene solution (k /kjj = 1.5, 1.0, 3.3 and-4.4, respectively). As it has b n mentioned that all such reactions are base catalyzed, it is difficult to understand why the reaction with m-toluidine does not display an isotope effect. As shown in Section 4.4, azo coupling reactions with aromatic amine may be rather complex with respect to mechanism. A critical discussion of Sziman and Messmer s paper is therefore impossible. Although announced in their conununication, a full paper has to the best of our knowledge, never been published. 

An acidic solution of 2,4-dinitrophenylhydrazine reacts with N-p-chlorophenyl-sulfonyl-3-ethoxy-l,2-thiazetidine 1-oxide to give (80%) the bis-2,4-dinitrophenyl-hydrazone of glyoxal. The adduct of A-sulfinyl-p-chlorophenylsulfonamide with dihydropyran is inert to catalytic hydrogenation and bromination. Treatment of two l,2-thiazetidine-3-one 1-oxides (e.g., 421) with hydriodic acid results in ring-cleavage and loss of sulfur. They are not oxidized to 1,1-dioxides by peracetic acid, ° but m-chloroperbenzoic acid accomplishes this oxidation. The unstable adducts with ketene decompose to amides with loss of hydrogen sulfide and sulfur dioxide or may be trapped by reaction with aromatic amines as shown for thiazetidine 1-oxide 422.An aldol-type condensation has been reported for A -cyclohexyl-1,2 thiazetidine-3-one 1-oxide and p-(A(A"-dimethylamino)benz-aldehyde. " Sulfur monoxide is lost in the flash-vacuum thermolysis of 422a. ... 

The JV-chloroethylphosphazene CCl3CCl2N=PCl3 generally undergoes reactions with aromatic amines at both phosphorus and a-carbon atoms ... 

Reaction with aromatic amines. A solution of the 2-aryl-5,8-dichloropyrimido[4,5-t/]pyridazine (1.0 g,... 

Nucleophilic displacement of chlorine, in a stepwise manner, from cyanuric chloride leads to triazines with heteroatom substituents (see Section 6.12.5.2.4) in symmetrical or unsymmetrical substitution patterns. New reactions for introduction of carbon nucleophiles are useful for the preparation of unsymmetrical 2,4,6-trisubstituted 1,3,5-triazines. The reaction of silyl enol ethers with cyanuric chloride replaces only one of the chlorine atoms and the remaining chlorines can be subjected to further nucleophilic substitution, but the ketone produced from the silyl enol ether reaction may need protection or transformation first. Palladium-catalyzed cross-coupling of 2-substituted 4,6-dichloro-l,3,5-triazine with phenylboronic acid gives 2,4-diaryl-6-substituted 1,3,5-triazines <93S33>. Cyanuric fluoride can be used in a similar manner to cyanuric chloride but has the added advantage of the reactions with aromatic amines, which react as carbon nucleophiles. New 2,4,6-trisubstituted 1,3,5-triazines are therefore available with aryl or heteroaryl and fluoro substituents (see Section 6.12.5.2.4). 

Cyanuric fluoride behaves much the same as cyanuric chloride but its higher reactivity leads to nucleophilic reactions with aromatic amines, which act as carbon nucleophiles. This is a useful advantage for cyanuric fluoride, as a synthetic reagent, for the synthesis of these triazine derivatives with carbon substituents. 

The range of nucleophiles that can participate in nucleophilic aromatic substitution is similar to the range of those that participate in, 1 reactions and includes alkoxides, " phenoxides, sulfides, fluoride ion, and amines. For reaction with aromatic amines with l-chloro-2,4-dinitrobenzene, the value of p is —4.0, indicting a substantial buildup of positive charge at nitrogen in the TS. Substitution by carbanions is somewhat less common. This may be because there are frequently... 

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