Synthesis, characterization, and ligand behaviour of a new ditelluroether (C₁₀H₇)Te(CH₂)₄Te(C₁₀H₇) and the concurrently formed ionic [(C₁₀H₇)Te(CH₂)₄]Br

Abstract

The reaction of 1-naphthyl bromide with n-butyl lithium, elemental tellurium, and 1,4-dibromobutane in THF affords both (CH)Te(CH)Te(CH) (1) and [(CH)Te(CH)]Br (2) in good yields. 1 is preferentially formed at low temperatures and is a rare example of a structurally characterized ditelluroether in which the tellurium atoms are bridged by a hydrocarbon chain. In the solid state, 1 shows secondary bonding TeTe interactions, which connect the molecules into layers which are further linked to 3-dimensional frameworks by TeH hydrogen bonds. [(CH)Te(CH)]Br (2) is formed concurrently during the synthesis of 1 and is the main product, when the reaction is carried out at room temperature. The revPBE/def2-TZVPP calculations of the reaction profiles indicate that the formation of 2 is somewhat more favourable than that of 1. Furthermore, at room temperature the activation energy for the formation of 2 is lower than that of 1. At low temperatures the activation energy of the reaction leading to 1 is lower than that to 2, which is consistent with the synthetic observations. When 1 was treated with CuBr, [Cu(μ-Br){μ-(CH)Te(CH)Te(CH)}] (3) was formed. It crystallizes as two polymorphs (3a) and (3b) in which both the packing and the conformation of the ditelluroether ligands are different. The reaction of 1 with HgCl produces [(CH)Te(CH)][HgCl]·CHCl (4·CHCl) and that of 1 with CuCl affords [(CH)Te(CH)]Cl (5). 2 and 5 are isomorphous.

Hybrid Quinoline Telluroether Ligand Derived Copper and Silver Complexes: Synthesis, Structural and Electronic Properties

“…The tellurium atoms show a weak intermolecular Te1⋅⋅⋅Te1 [3.7642(8) Å] interactions as well as intermolecular N1⋅⋅⋅Te1 [3.595(3) Å] interactions with zig‐zag fashion (Figure S24 SI). The intermolecular Te⋅⋅⋅Te interactions is shorter than the sum of the van der Walls radii of tellurium (4.40 Å) and also shorter than the reported values of 3.87(7) Å, [47] and 3.9124(15)–718(16) Å [3] . The intermolecular Te⋅⋅⋅N distance 3.593(3) Å is longer than the interactions observed in previous reports 2.340(3)–2.743(5) Å [46–50] …”

“…These interactions lead to arrange the molecules 5 in sine wave three-dimensional supramolecular network (Figure S25a, SI). [3] .…”

“…It has been observed that the copper ion has preferably bonded with soft tellurium instead of sulphur. [3,23] They also have reported naphthalene based bidentate tellur-oether (C 10 H 7 )Te(CH 2 ) 4 Te(C 10 H 7 ), which is associated with CuBr salt to afford a self-assembled macrocyclic complex. [3] Similarly Liaw's group has reported an interesting silver complex which exhibited a chair conformation.…”

“…[3,23] They also have reported naphthalene based bidentate tellur-oether (C 10 H 7 )Te(CH 2 ) 4 Te(C 10 H 7 ), which is associated with CuBr salt to afford a self-assembled macrocyclic complex. [3] Similarly Liaw's group has reported an interesting silver complex which exhibited a chair conformation. [24] Recently, Lang and co-workers have reported bis(2-bypyridyl) ditellane I and its bimetallic copper complex (Figure 1) where copper ion adopted a tetrahedral geometry and tellurium atoms adopted trigonal pyramidal geometry.…”

“…[1,2] The polytelluroethers have been relatively less studied as compared with their polythioether and polyselenoether analogues because of their poor stability and easy decomposition at room temperature in the oxygen environment due to weak CÀ Te bond and low oxidation potential of tellurium. [3,4] Several research groups have reported the synthesis of monodentate, and multidentate hybrid telluroether ligands and studied their coordination behaviour with various transition metal ions such as; Ru, Rh, Ni, Pd, Pt, Cu and Ag. [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] However, the isolation of bimetallic complexes has not been explored well despite their interesting structural properties and scope of the study of the metal•••metal interactions.…”