Pyridine tris amines

The synthetic and industrial importance of this reaction lies in its generality, and the ease with which the amino substituent in the products can be subsequently transformed into other functionalities. Pyridine itself is more difficult to aminate than quinoline or isoquinoline, and it does not react with potassium amide in liquid ammonia even on prolonged treatment. However, pyridine is aminated in good yield by sodamide in toluene, and di- and tri-amination can be achieved with excess sodamide at higher temperatures. The 4-position is substituted last in triamination y-amination is very difficult indeed and only takes place when all a -positions are occupied. 

Involvement of two nucleophilic nitrogen atoms is thus typical for the amino heterocycles. The mutual disposition of the pyridine and amine nitrogen atoms allows the formation of chelate structures for the cobalt complexes of purine, 221 and 222. Structures with the N, iV -five-membered metal cycles were proven for the tri- and tetranuclear complexes of silver ) with 8-aminoquinoline (223) (92IC4370), and polymeric copper- and rhodium-acetate clusters (224). Another coordination mode can be found in the complexes of 4-amino-3,5-bis(pyridin-2-yl)-l,2,4-triazole, (225 or... 

The trichloromethyl group in s-triazines is sufficiently reactive to he displaced by ammonia, amines, or alkoxides even if two deactivating groups have already been introduced. In contrast, under much more vigorous conditions benzotrichloride and 2,6-bis(trichloro-methyl)pyridine are unreactive towards ammonia in dimethyl-formamide (2 hr, 165°). Tris-amination of 2,4,6-tris-(trichloro-methyl)-s-triazine is complete in aprotic, but not in protic, solvents. 

Di-t-butyl chromate and its pyridine adduct are suitable for large-scale oxidations of alcohols to ketones, thus cyclododecanol was converted into cyclododecanone (97 Alcohols are easily separated from non-hydroxylic compounds via their calcium chloride complexes. This method was used to separate cyclododecanone and cyclododecanol and is suitable for the separation of large quantities of material." All-cis-cyclododecane-l,5,9-triol was converted into the all-cis-tri-amine by tosylation, azide substitution, and reduction, and the amine acylated with 2,3-dimethoxybenzoyl chloride to give the tri-amide, an analogue of enterochelin. ... 

Zincate reagents can add to imines with or without Lewis acid catalysis. Alkylimines require BF3 but imines of pyridine-2-carboxaldehyde react directly. If the imines are derived from chiral amines, diastereoselectivity is observed. Both a-phenylethyl amine and ethyl valinate have been tried. Higher enantioselectivity was observed with mixed magnesium reagents.175... 

New examples of the preparation of stannylamines, largely by established methods, are shown in Equations (164) and (165). Sodium bis(trimethylstannyl)amine can be prepared from sodium amide and a stannylamine,499 and can act as the precursor to other bis- and tris(stannyl)amino compounds.499 500 The tristannylamines are planar about the nitrogen, with the unshared pair in a 2p orbital. Tris(chlorodimethylstannyl)amine, with five-coordinate tin, is close to centrosymmetrical, and reacts with pyridine to give a tetrastannabicyclo[3.1.1]heptane.501... 

Benzoylation of )V-(2,2-diethoxycarbonylvinyl)-/3-D-galactopyranosy-lamine and -/3-D-gluco analogue in pyridine with benzoyl chloride afforded mixtures of di-, tri-, and tetra-O-benzoyl derivatives. From 2,3,6-tri-O-benzoyl-N-(2,2-ethoxycarbonylvinyl)-j8-D-galatopyranosylamine and -/3-D-glucopyranosylamine the amines were liberated with bromine or chlorine in chloroform or methylene chloride (89MI4). 

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