Cyclic di[(o-polyethyleneglycoxy)phenyl]amine: new members in the crown ether family

The synthesis of cyclic ethers based on polyethyleneglycol chains grafted on di(o-hydroxyphenyl)amine is described. The starting diarylamine is obtained from a melted salt procedure and coupled to the tosylated tri-, tetra- and pentaethyleneglycol. The X-ray crystal structure of the tetraethyleneglycol derivative was determined. For the triethyleneglycol compound, alkylation of the nitrogen atom with 5-bromomethyl-5′-methyl-2,2′-bipyridine (excess or 1 equiv.) led either to the quaternary ammonium salt or to the tertiary amine derivatives, respectively. The latter reacted with [Re(CO)5Cl] to give the corresponding Re(I) complex in a facial configuration.