Macrocyclic polyamines

DETAILED DESCRIPTION OF THE INVENTION Macrocyclic polyamines which form stable complexes with metal ions are known.
The present invention is directed to macrocyclic polyamines in which complex formation is hindered by (1) asymmetric distribution of nitrogen atoms in the ring, and/or (2) the provision of nitrogen atoms in excess of that required for stable complexation.
The destabilized complexes can be employed to generate free amine thermally and are hence thermally activated initiators for the curing of epoxy resins.
The macrocyclic amines of the present invention can be made by condensation of a suitable di-terminal amine sulfonamide alkali metal salt with a di-terminal halide or a di-terminal sulfonate ester in a polar aprotic solvent.
The reaction is preferably carried out at 50.
degree.
C to 120.
degree.
C.
Preferred solvents are dimethylformamide and dimethylsulfoxide.
The preferred alkali metal salts are sodium salts of the di-terminal amine sulfonamides.
Using the preferred metal salts, it is not necessary to employ high dilution techniques to obtain good yields of product.
Preferred concentration of the alkali metal salts (and of the di-terminal dihalide and di-terminal sulfonate ester) in the above solvents is 0.
05-0.
5 mole/liter.
The products formed by the above reaction are the N-toluenesulfonamide (N-tosyl) derivatives of the macrocyclic polyamines.
These products can be hydrolyzed to the parent amines by warming a 20% solution of the tosyl derivative in 97% sulfuric acid at 95.
degree.
-100.
degree.
C until a sample gives a clear solution in alkaline water, generally about 1-48 hours.
Dilution of the reaction mixture with ether yields the dihydrosulfate salts which can be converted to the free base or, for the purpose of characterization, to the hydrochloride salts, by treatment with ion-exchange resin.
Metal complexes of the above amines can be prepared by treating a solution of the hydrochloride or dihydrosulfate salts with a stoichiometric amount of the metal salt.
The mixture is neutralized and evaporated