Thallium macrocyclic chemistry: synthesis and crystal structures of [Tl([18]aneN2S4)]PF6 and [Tl([18]aneS6)]PF6([18]aneN2S4= 1,4,10,13-tetrathia-7,16-diazacyclooctadecane, [18]aneS6= 1,4,7,10,13,16-hexathiacyclooctadecane)

Abstract

Reaction of TIPF₆ with 1 molar equivalent of L (L =[18]aneN₂S₄ or [18]aneS₆) in refluxing MeCN followed by addition of diethyl ether affords the 1 : 1 complex [TlL]PF₆ in high yield. The complex [Tl([18]aneN₂S₄)]PF₆ crystallises in the triclinic space group P with a= 9.733(6), b= 9.775(6), c= 11.370(8)Å, α= 102.68(4), β= 92.35(4), γ= 95.05(5)° and Z= 2. The structure shows the thallium(I) ion occypying the ‘cardle’ formed by the macrocycle and bound via an [N₂S₂+ S₂] donor set, Tl–S(4) 3.1299(13), Tl–S(13) 3.1445(13), Tl–N(7) 2.834(4), Tl–N(16) 2.992(4), Tl ⋯ S(1) 3.4778(15) and Tl ⋯ S(10) 3.4739(14)Å. This leaves the top face of the metal centre exposed, except for long-range interactions with two further thioether donor atoms from adjacent [Tl([18]aneN₂S₄)]⁺ cations, Tl ⋯ S(1′) 3.643(1)(related by 1 –x, 1 –y, 1 –z), Tl ⋯ S(10″) 3.676(1)Å(related by 1 –x, 1 –y, -z), and one F atom of the PF₆^– counter-ion, Tl ⋯ F(1) 3.326(4)Å. The complex [Tl([18]aneS₆)]PF₆ crystallises in the monoclinic space group P2₁/c with a= 11.0279(13), b= 18.617(5), c= 10.8568(13)Å, β= 96.876(13)° and Z= 4. The structure shows Tl^I interacting with all six macrocyclic thioether donors; two of those interactions, Tl–S(1) 3.164(5) and Tl–S(13) 3.205(7)Å, being considerably shorter than the other four, Tl ⋯ S(4) 3.370(5), Tl ⋯ S(7) 3.315(6), Tl ⋯ S(10) 3.347(7) and Tl ⋯ S(16) 3.356(6)Å. There are additional long-range interactions with two further thioether donors from adjacent [Tl([18]aneS₆)]⁺ cations, Tl ⋯ S(7prime;) 3.689(6)(related by –x, 1 –y, 1 –z) and Tl ⋯ S(16″) 3.688(6)Å(related by 1 –x, 1 –y, 1 –z). There is also a long-range contact with one F atom of the PF₆^– counter-ion, Tl ⋯ F(6) 3.052(24)Å.