Synthesis of an N, N-diethyl-tert-butylazothioformamide ligand and coordination studies with Copper(I) salts

Evaluating Coordinative Binding Mechanisms through Experimental and Computational Studies of Methoxy‐Substituted Arylazothioformamide Copper(I) Complexes

“…Mechanistic investigations commenced with the modelling of found complexes (i. e., (11) and ( 12)) using B3LYP/6-311G + + (d,p)//B3LYP/6-31G(d,p) to predict the single point energy and geometry optimizations of the isolated structures and other possible structures (either (exo-X and halogen-bridged symmetric μ-X dimer;, or μ-X "butterfly" dimer) as shown in Figure 6 as to describe each found complex as thermodynamically or kinetically favored. The computations were run in various solvents (e. g., THF and acetonitrile) as triplets.…”

“…Complexes were prepared by dissolving each ligand in THF, acetonitrile, or chloroform followed by addition of salt (Cu I Br, Cu I I, or [(CH 3 CN) 4 Cu I ](BF 4 )) in either a 2 : 1 or 1 : 1 stoichiometric ratio, respectively, and then gently heating to encourage solvation and /or simply allowing each solution to evaporatively concentrate and recover crystalline material. X-ray crystal structures (11)(12)(13) were obtained from mixing Cu I salts with para-methoxy ATF (6) as shown in Figure 3 (Diffraction data can be found in the ESI Table S2). Firstly, in contrast to structures (2 a/b) and (3 a/b), ligand (6) when mixed with an equimolar amount of Cu I Br gave dimeric exo-Br structure (11) in 44 % yield.…”

“…X-ray crystal structures (11)(12)(13) were obtained from mixing Cu I salts with para-methoxy ATF (6) as shown in Figure 3 (Diffraction data can be found in the ESI Table S2). Firstly, in contrast to structures (2 a/b) and (3 a/b), ligand (6) when mixed with an equimolar amount of Cu I Br gave dimeric exo-Br structure (11) in 44 % yield. This monoclinic exo-Br complex (11) crystallized in a C 2c space group where all bond distances and bond angles are identical for each 6•CuBr pair (a true 1 : 1 dimer).…”

“…Coordinative investigations of Cu I halides, both Cu I Br and Cu I I, and non‐coordinating [(CH 3 CN) 4 Cu I ](BF 4 ) with ATF ligands (1 a/b) in organic solvents produced 1 : 1 μ‐X halogen‐bridged dimers (2 a/b) and (3 a/b ) from halide salts (i. e., 2 : 2 complexes), and 2 : 1 complexes (4 a/b) with non‐coordinative tetrafluoroborate counterions, respectively (Figure 1). All complexes (2 a/b) , (3 a/b) , and (4 a/b) exhibited unchanged oxidation states of both the ligands (neutral) and metal (1+) [10,11] …”

“…All complexes (2 a/b), (3 a/b), and (4 a/b) exhibited unchanged oxidation states of both the ligands (neutral) and metal (1 +). [10,11] Follow-up investigations on a series of para-substituted ATFs with varying electron-donating or withdrawing strength monitored through UV-Vis binding association studies found that the presence of electron-donating groups (para-EDGs) produce stronger binding affinities than para-EWGs. [12] Additionally, the binding association values for all complexes gave less error when fit to all types of 2 : 1 non-linear binding models (Full, Additive, Non-Cooperative, and Statistical) with higher error found in the 1 : 1 non-linear binding model.…”