The influence of substituents (R) at N 1 atom of thiophene-2-carbaldehyde thiosemicarbazones {(C 4H 3S)HC 2[dbnd]N 3–N(H)–C 1( [dbnd]S)N 1HR} on bonding, nuclearity and H-bonded networks of copper(I) complexes

Abstract

The nuclearity, bonding and H-bonded networks of copper(I) halide complexes with thiophene-2-carbaldehyde thiosemicarbazones {(C 4H 3S)HC 2 N 3–N(H)–C 1( S)N 1HR} are influenced by R substituents at N 1 atom. Thiophene-2-carbaldehyde-N 1-methyl thiosemicarbazone (HttscMe) or thiophene-2-carbaldehyde-N 1-ethyl thiosemicarbazone (HttscEt) have yielded halogen-bridged dinuclear complexes, [Cu 2(μ-X) 2(η 1-S-Htsc) 2(Ph 3P) 2] (Htsc, X: HttscMe, I, 1; Br, 2; Cl, 3; HttscEt, I, 4; Br, 5; Cl, 6), while thiophene-2-carbaldehyde-N 1-phenyl thiosemicarbazone (HttscPh) has yielded mononuclear complexes, [CuX(η 1-S-HttscPh) 2] (X, I, 7a; Br 8; Cl, 9) and a sulfur bridged dinuclear complex, [Cu 2(μ-S-HttscPh) 2(η 1-S-HttscPh) 2I 2] 7b co-existing with 7a in the same unit cell. These results are in contrast to S-bridged dimers [Cu 2(μ-S-Httsc) 2(η 1-Br) 2(Ph 3P) 2] · 2H 2O and [Cu 2(μ-S-Httsc) 2(η 1-Cl) 2(Ph 3P) 2] · 2CH 3CN obtained for R = H and X = Cl, Br (Httsc = thiophene-2-carbaldehyde thiosemicarbazone) as reported earlier. The intermolecular CH Ph⋯π interaction in 1– 3 (2.797 Å, 1; 3.264 Å, 2; 3.257 Å, 3) have formed linear polymers, whereas the CH Ph⋯X and N 3⋯HCH interactions in 4– 6 (2.791, 2.69 Å, 5; 2.776, 2.745 Å, 6, respectively) have led to the formation of H-bonded 2D polymer. The PhN 1H⋯π, interactions (2.547 Å, 8, 2.599 Å, 9) have formed H-bonded dimers only. The Cu⋯Cu separations are 3.221–3.404 Å ( 1– 6).