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The synthesis of 2,6-disubstituted N,N,N',N'-tetramethyl-p-phenylenediamines (R ~Cl, Br, I, CN, or CMCSi(CH 3 ) 3 ), potential precursors/building blocks for molecular magnets, is presented. In addition to standard methods ( 1 H NMR, 13 C NMR, MS, IR, UV), the products were also characterised by means of cyclic voltammetry. Completely reversible electrochemical behaviour was observed for both the CN and the CMCSi(CH 3 ) 3 derivatives. Moreover, the corresponding radical cations and the dications were observed by cyclic voltammetry for these compounds. The first oxidation step of the Cl and the Br derivatives was also found to be reversible, although a chemical side reaction was detected after oxidation to the corresponding dication. The radical cation could not be detected for the I derivative. In this case direct oxidation to the dication followed by a chemical reaction was observed.

Summary: Poly(ethylene oxide) methyl ether 4H‐1,2,4‐triazol‐4‐yl (1) has been synthesized as a novel macroligand. ESI‐MS (electrospray ionisation mass spectrometry), MALDI‐TOF (matrix‐assisted laser desorption ionisation time‐of‐flight) MS as well as NMR spectroscopy were used for the accurate determination of number‐average molecular weights ($\overline M _{\rm n}$), the crucial parameter for subsequent synthesis of metal‐polymer complexes of four different samples 1a–d. Reaction of polymer 1a with [Fe(H2O)6](nps)2 (nps = 3‐nitrophenylsulfonate) gave [Fe(1a)3](nps)2, a bistable metal‐polymer complex that exhibited low‐spin (LS) to high‐spin (HS) transitions around T1/2 = 257 K, accompanied by a change in colour from violet (LS) to slightly yellow (HS).

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