The novel enantiopure dipyridyl spacer 2,2′-dimethoxy-1,1′-binaphthyl-3,3′-bis(4-pyridyl-amido) (R)-L has\udbeen designed as a robust source of axial chirality to obtain helical coordination polymers. The reaction of\ud(R)-L and the differently substituted dithiophosphato complexes [Ni((RO)2PS2)2] [R = Me (1), Et (2)] efficiently\udyielded coordination polymers (1·L)∞ and (2·L)∞, respectively, consisting of helical chains in which the nickel(II)\udions of the [Ni((RO)2PS2)2] units are bridged by the enantiopure L ligands. The obtained polymers differ in\udterms of the configuration at the metal centres, which is trans and cis for (1·L)∞ and (2·L)∞, respectively.\udThe cis configuration in (2·L)∞ generates a further element of chirality around the metal center, which\udoccurs stereospecifically, as only one enantiomeric form is present, with homochiral helices packed with\udopposite screw sense in the crystal. The electronic and structural features of L, (1·L)∞, and (2·L)∞ have\udbeen investigated by means of DFT theoretical calculations, and the theoretical results have been\udcompared with the experimental ones coming from single-crystal X-ray diffraction. The cis/trans isomerism\uddisplayed by the metal centers in (1·L)∞ and (2·L)∞ has been tentatively explained on the basis of the\udresults of theoretical calculations performed on hypothetical pentacoordinated intermediates.
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