The isomers 4′-(4-(trifluoromethyl)phenyl)-4,2′:6′,4″-terpyridine (
1), 4′-(3-(trifluoromethyl)phenyl)-4,2′:6′,4″-terpyridine (
2), 4′-(4-(trifluoromethyl)phenyl)-3,2′:6′,3″-terpyridine (
3), and 4′-(3-(trifluoromethyl)phenyl)-3,2′:6′,3″-terpyridine (
4) have been prepared and characterized. The single crystal structures of
1 and
2 were determined. The 1D-polymers [Cu
2(hfacac)
4(
1)
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The isomers 4′-(4-(trifluoromethyl)phenyl)-4,2′:6′,4″-terpyridine (
1), 4′-(3-(trifluoromethyl)phenyl)-4,2′:6′,4″-terpyridine (
2), 4′-(4-(trifluoromethyl)phenyl)-3,2′:6′,3″-terpyridine (
3), and 4′-(3-(trifluoromethyl)phenyl)-3,2′:6′,3″-terpyridine (
4) have been prepared and characterized. The single crystal structures of
1 and
2 were determined. The 1D-polymers [Cu
2(hfacac)
4(
1)
2]
n·2
nC
6H
4Cl
2 (Hhfacac = 1,1,1,5,5,5-hexafluoropentane-2,4-dione), [Cu(hfacac)
2(
2)]
n·2
nC
6H
5Me, [Cu
2(hfacac)
4(
3)
2]
n·
nC
6H
4Cl
2, [Cu
2(hfacac)
4(
3)
2]
n·
nC
6H
5Cl, and [Cu(hfacac)
2(
4)]
n·
nC
6H
5Cl have been formed by reactions of
1,
2,
3 and
4 with [Cu(hfacac)
2]·H
2O under conditions of crystal growth by layering and four of these coordination polymers have been formed on a preparative scale. [Cu
2(hfacac)
4(
1)
2]
n·2
nC
6H
4Cl
2 and [Cu(hfacac)
2(
2)]
n·2
nC
6H
5Me are zig-zag chains and the different substitution position of the CF
3 group in
1 and
2 does not affect this motif. Packing of the polymer chains is governed mainly by C–F...F–C contacts, and there are no inter-polymer π-stacking interactions. The conformation of the 3,2′:6′,3″-tpy unit in [Cu
2(hfacac)
4(
3)
2]
n·
nC
6H
4Cl
2 and [Cu(hfacac)
2(
4)]
n·
nC
6H
5Cl differs, leading to different structural motifs in the 1D-polymer backbones. In [Cu(hfacac)
2(
4)]
n·
nC
6H
5Cl, the peripheral 3-CF
3C
6H
4 unit is accommodated in a pocket between two {Cu(hfacac)
2} units and engages in four C–H
phenyl...F–C
hfacac contacts which lock the phenylpyridine unit in a near planar conformation. In [Cu
2(hfacac)
4(
3)
2]
n·
nC
6H
4Cl
2 and [Cu(hfacac)
2(
4)]
n·
nC
6H
5Cl, π-stacking interactions between 4′-trifluoromethylphenyl-3,2′:6′,3″-tpy domains are key packing interactions, and this contrasts with the packing of polymers incorporating
1 and
2. We use powder X-ray diffraction to demonstrate that the assemblies of the coordination polymers are reproducible, and that a switch from a 4,2′:6′,4″- to 3,2′:6′,3″-tpy metal-binding unit is accompanied by a change from dominant C–F...F–C and C–F...H–C contacts to π-stacking of arene domains between ligands
3 or
4.
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