Intermolecular reactions amine compounds

Unlike the intermolecular reaction, the intramolecular aminopalladation proceeds more easily[13,14,166], Methylindole (164) is obtained by the intramolecular exo amination of 2-allylaniline (163). If there is another olefinic bond in the same molecule, the aminopalladation product 165 undergoes intramolecular alkene insertion to give the tricyclic compound 166[178]. 2,2-Dimethyl-l,2-dihydroquinoline (168) is obtained by endo cyclization of 2-(3,3-dimethyiallyl)aniline (167). The oxidative amination proceeds smoothly... 

These fragments either combine intramolecularly to form the ortho and para nitro compounds or dissociate completely and then undergo an intermolecular reaction to form the same products. The theory was not developed to include a detailed transition state and no mention was made of how the para isomer was formed. Reduction of the cation-radical could give the amine (which was observed experimentally76), but one would expect the concurrent formation of nitrogen dioxide and hence nitrite and nitrate ions however, the latter has never been... 

Unfortunately, in many cases the reaction is not so straightforward it becomes complicated because of the nature of the activated component. There is another nucleophile in the vicinity that can react with the electrophile namely, the oxygen atom of the carbonyl adjacent to the substituted amino group. This nucleophile competes with the amine nucleophile for the electrophilic center, and when successful, it generates a cyclic compound — the oxazolone. The intermolecular reaction (path A) produces the desired peptide, and the intramolecular reaction (path B) generates the oxazolone. The course of events that follows is dictated by the nature of the atom adjacent to the carbonyl that is implicated in the side reaction. 

Discovered over a century ago, electrophilic mercuration is probably the oldest known C-H bond-activation reaction with a metal compound. The earliest examples of aromatic mercuration were reported by Volhard (mercuration of thiophene) [1], Pesci (mercuration of aromatic amines) [2], and Dimroth [3], who was the first to mercurate benzene and toluene, generalize the reaction, and assign the correct structures to the products originally observed by Pesci. Since the work of Dimroth electrophilic aromatic metalation reactions with compounds of other metals, for example Tl(III), Pb(IV), Sn(IV), Pt(IV), Au(III), Rh(III), and Pd(II), have been discovered [4], In this chapter, we will focus on intermolecular SEAr reactions involving main-group metal electrophiles and resulting in the formation of isolable metal aryls which find numerous important applications in synthesis [5], Well-known electrophilic cyclometalation reactions, for example cyclopalla-dation can be found in other chapters of this book and will not be reviewed here. 

A one-pot synthesis of 3,5-disubstituted 7-hydroxy-3//-l,2,3-triazolo[4,5-d]pyrimidines (130) has been carried out by using benzyl azide, cyano-acetamide, ethyl or methyl esters of the appropriate carboxylic acid, and sodium ethoxide as catalyst. The reaction proceeds via a 5-amino-l-benzyltriazole-4-carboxamide intermediate (85JHC1607). 7-Amino-3H-l,2,3-triazolo[4,5-d]pyrimidines 133 (R2 = H) were prepared starting from benzyl azide, malononitrile, and an aliphatic or aromatic nitrile, or by reaction of 130 with phosphorus oxychloride followed by amination. Compound 132 was formed in most reactions from two molecules of the 5-amino-4-cyano-l-benzyltriazole intermediate by an intermolecular nucleophilic at-... 

Meth-Cohn and co-workers derived strong chemical support for the singlet nitrene carbazole pathway from a study of the thermolysis and photolysis of the azide 246.306 Here, the nitrene 247 has two intramolecular pathways open to it, namely, formation of carbazole (249) or phenanthridine (250) apart from intermolecular reactions leading to amine and azo compound (Scheme 48). 

Scheme 42.10 Organocatalytic domino sulfa-Michael/amination process by way of an iminium ion-enamine sequence both catalytic steps are intermolecular reactions. Protocol point compound 34 was added after 30 min.

The tertiary amine is formed in a similar manner from the imine and a secondary amine. This side reaction can be minimized by carrying out the hydrogenation in the presence of ammonia, which tends to shift the equiHbrium back towards the imine. When a compound with two or more nitrile groups is hydrogenated, the formation of both cycHc and acycHc secondary and tertiary amines is possible, depending on whether the side reaction is intramolecular or intermolecular. For example, for the hydrogenation of adiponitfile ... 

In the reaction of 4-diazotriazoles with morpholine, pyrrolidine [83DIS(B)(43)2557], and several other secondary amines (66JMC733), the corresponding triazenes 247 were obtained. Also, in the case of 4-diazo-l,2,3-triazole-5-carboxamide, these compounds could easily be obtained in organic solvents despite the competing intramolecular ring closure to 2,8-diazahypoxanthine. In aqueous media, the intermolecular coupling... 

---