Synthesis and crystal structure of copper (I) sulfamate π-complex with 5-methyl-N-(Allyl)-1,3,4-thiadiazol-2-amine of [Cu2(C6H10N3S2)2(NH2SO3)2] composition

Abstract

[Cu 2 ( Mepeta ) 2 (NH 2 SO 3 ) 2 ] compound has been obtained by means of alternating current electrochemical technique starting from the mixture of propanolic solution of 5-methyl- N -(allyl)-1,3,4-thiadiazol-2-amine ( Mepeta ) and water solution of Cu(NH 2 SO 3 ) 2 ·xH 2 Oand later X-ray structurally characterized by single crystal method. High-quality crystals of the compound appeared in three days. The compound crystallizes in the triclinic system: Sp. gr. – P -1, a = 7.799(2), b = 8.054(3), c = 10.165(2) Å, α = 96.003(7), β = 109.17 (3), γ = 112.95(3)°, V = 535.2 (3) Å 3 ,Z = 1, D х = 1.954(3) g/sm 3 , R ( F ) = 0.056 for 2052 independent reflections with F ≥ 4 σ ( F ). In the structure 1 , organic molecule Mepeta acts as chelate-bridging tridentate ligand being connected to copper (I) by two N atoms of thiadiazo leringand (C=C)-bond fromallyl-group, resulting in a formation of stable cationic dimers [Cu 2 ( Mepeta ) 2 ] 2+ . In the structure 1 , N atom from sulfamate-anion occupies an apical position of the metal coordination polyhedron. The efficiency of Cu(I)-(C=C) interaction is confirmed by the fact that allylic C=C bond is slightly elongated to 1.355(7) Å. Selected bond length (in Å) and angle (in deg) values: Cu1–N3 2.092(3), Cu1–N4 i 1.998(4), Cu1–N1 2.267(4), Cu–m 1.965(4) (m –middle point of C7=C8 bond), C8–C9 1.355(7), N4 i –Cu1–N3 112.8(3), N4 i –Cu1–N1 95.5(4), N4 i –Cu1– m 130.5(2), N3–Cu1–N1 86.5(3), N3–Cu1– m 109.6(3). Despite the presence of sulfamate anion NH 2 SO 3 – N-atom, thiadiazole ligand participates in the formation of stable tectone [Cu 2 ( L ) 2 ] 2+ previously found in the structures of other Сu(I) π-complexes with allyl derivatives of 1,3,4-thiadiazole. Hydrogen bonds N-H···O play an additional stabilizing role in the formation of hydrogen-bonded chains. Keywords : copper (I), sulfamate anion, π-complex, 1,3,4-thiadiazole, crystal structure.