Nucleophilic ring opening of bis-and tris(1-oxa-3,5-diazinium) salts 1 with n-propylamine leads to the bis-and tris-(armed) oligonitrile derivatives 3 and 8 with secondary amino groups in the side chain. Alternatively, treatment of simple 1-oxa-3,5-diazinium salts 2 with primary and secondary diand triamines offers a convenient pathway for the synthesis of bis-and tris(armed) oligonitriles 4, 5 and 7. 2,6-Diaminopyridine furnishes the new pincer-type ligand 6 upon reaction with 1-oxa-3,5-diazinium salt 2a. Multivalent oligonitriles 4, 6, 7 and 8 containing secondary amino groups are able to form intra-and intermolecular hydrogen bonds in the

Nucleophilic ring opening of the 1-oxa-3,5-diazinium salts 2 and 3 by propylamine furnishes the new polydentate, branched, pincer-type ligands 4 and 5, respectively, in 34 and 57 % yield. The 1-oxa-3,5-diazinium salts 2 and 3 were prepared from pyridine-2,6-dicarbonyl dichloride (1) by treatment with dimethylcyanamide and diisopropylcyanamide in the presence of antimony pentachloride and tin tetrachloride, respectively. The structure of 4, which is characterised by a strongly twisted N-acyloligonitrile arm, was determined by X-ray crystallography. The ligand 4, with its short and long arms, forms chelate complexes 4 -·Pd(OAc) + and 4·CuCl 2 when treated with palladium(II) acetate and copper(II) chloride, respectively. 4 -·Pd(OAc) + shows remarkable catalytic