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A series of macrocyclic polyether (crown) ligands containing the proton‐ionizable s‐triazole subcyclic unit were prepared by reacting the 1‐THP blocked 3,5‐bis(chloromethyl)‐1H‐1,2,4‐triazole with various oligoethylene glycols. The starting bis(chloromethyl)triazole is a vessicant and must be used with caution. Triazolo‐18‐crown‐6 (5) formed stable complexes with barium, strontium, copper and benzylammonium cations but not with potassium or lithium. The crystal structure of 5 showed the triazole proton to be on nitrogen 3 which is outside the macroring cavity.

Two new reactive aza crown ethers, (1) and (2), containing the 4-hydroxypyridine unit have been prepared and found to be different with respect to pK(HpO) values for H2L+, structures of the hydrates of HL, and complex formation with benzylamine and the benzylammonium ion.Crown ethers containing reactive groups are important as intermediates for the preparation of functionalized crown derivatives such as lariat ethers, bis(crown ethers), synthetic ionophores, immobilized crown ethers, and crown polymers. 1 Interest in these applications has resulted in the development of a variety of synthetic procedures for the preparation of hydroxymethyl crown ethers, which are representative of such compounds.2 We report here the synthesis of two new macrocycles (1) and (2). Each of these compounds contains the 4-hydroxypyridine unit, but their reactions, basicity, and structures are distinctly different.

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