Formation of Chain and Large-Ring Polymeric Metal Complexes by the “Extended Reach” Sulfur Donor Ligands N,N‘-Ethylenebis(pyrrolidine-2-thione) and N,N‘-p-Phenylenedimethylenebis(pyrrolidine-2-thione)

The preparations are reported of the “extended-reach” sulfur donor ligands N, N ‘-ethylenebis(pyrrolidine-2-thione) (EBPT) and N, N ‘- p -phenylenedimethylenebis(pyrrolidine-2-thione) ( p -XBPT) and of a range of complexes with Co II, Ni II, Cu II, Cu I, Zn II, Cd II, and Ag I, seven of which have been structurally characterized by X-ray crystallography. [Co(NCS) 2 (EBPT)] n crystallizes in the orthorhombic space group Pna 2 1, with a = 10.339(4) Å, b = 10.074(5) Å, c = 16.832(7) Å, and Z = 4. [ZnBr 2 (EBPT)] n crystallizes in the monoclinic space group P 2 1 /n, with a = 9.979(4) Å, b = 9.871(3) Å, c = 16.057(6) Å, β = 99.95(2)°, and Z = 8. Both of these complexes contain tetrahedrally coordinated metal ions linked by EBPT bridges to form chains. [CoCl 2 (EBPT)] 2 crystallizes in the tetragonal space group I 4 1 /acd, with a = b = 14.400(1) Å, c = 28.426(4) Å, and Z = 16. This compound forms discrete 18-membered rings. [CuCl(EBPT)] n crystallizes in the monoclinic space group C 2/ c, with a = 19.188(3) Å, b = 9.987(2) Å, c = 15.964(3) Å, β = 123.12(1)°, and Z = 8. In this compound each EBPT ligand employs one monodentate S atom and one μ 2 -S atom and forms ribbons of alternating Cu 2 (EBPT) 2 18-membered rings and four-membered Cu 2 (μ 2 -S) 2 rings. {[CuBr(EBPT)]·MeNO 2 } n crystallizes in the monoclinic space group C 2/ c, with a = 18.117(3) Å, b = 9.932(1) Å, c = 18.113(3) Å, β = 90.70(1)°, and Z = 4. This compound also has a ribbon structure, but here 18-membered Cu 2 (EBPT) 2 rings alternate with Br-bridged Cu 2 Br 2 units. [Ni(NO 3 ) 2 ( p -XBPT)] n crystallizes in the monoclinic space group C 2/ c, with a = 10.900(3) Å, b = 14.474(4) Å, c = 13.488(4) Å, β = 99.24(2)°, and Z = 4. The nickel atoms are bonded to two bidentate nitrates and two bridging p -XBPT ligands, forming chains. {[Co( p -XBPT) 2 ](ClO 4 ) 2 .4MeNO 2 } n crystallizes in the monoclinic space group C 2/ c, with a = 18.284(2) Å, b = 17.897(3) Å, c = 31.136(4) Å, β = 102.38(1)°, and Z = 8. Each Co is tetrahedrally coordinated to four sulfur atoms from four p -XBPT units which connect the metal centers into sheets of contiguous 52-membered rings. EBPT crystallizes in the monoclinic space group P 2 1 / n, with a = 5.479(2) Å, b = 9.560(4) Å, c = 11.171(7) Å, β = 95.79(2)°, and Z = 2; the thiolactam rings are coplanar and the sulfur atoms anti - disposed. The role of ligand conformation in determining structural types is discussed.