Three novel Cu6S6 cluster-based coordination compounds: synthesis, framework modulation and the sensing of small molecules and Fe3+ ions

• Published in: Dalton transactions : an international journal of inorganic chemistry Vol. 45; no. 29; pp. 11883 - 11891
• Main Authors: Song, Jiang-Feng, Li, Si-Zhe, Zhou, Rui-Sha, Shao, Jia, Qiu, Xiao-Min, Jia, Ying-Ying, Wang, Jun, Zhang, Xiao
• Format: Journal Article
• Language: English
• Published: 01.07.2016
• Subjects: Clusters; Construction; Coordination compounds; Diffraction; Displays; Formations; Infrared spectroscopy; X-rays
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c6dt02264b

Three novel Cu6S6 cluster-based coordination compounds formulated as [Cu super(I) sub(3)(mpymt)3]2 (1), {(Cu super(I) sub(4)Br4)[Cu super(I) sub(6)(mpymt)6]}n (2), and {(Cu super(I) sub(6)I6)[Cu super(I) sub(6)(mpymt)6]}n (3) (Hmpymt = 4-methylpyrimidine-2-thione), have been synthesized under solvothermal conditions and characterized by elemental analysis, infrared (IR) spectroscopy, thermal gravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. Structural analysis reveals that compound 1 shows a distorted octahedral core of six copper atoms (Cu6S6) constructed from four alpha and two beta type N&z.dbd; C-SH parts from six mpymt- anions. Compound 2 displays an interesting 3D framework constructed from Cu6S6 and Cu4Br4 Cu(i) clusters simultaneously, interestingly, six mpymt- with alpha type N&z.dbd; C-SH parts are involved in the formation of Cu6S6. Compound 3 displays an infinite 1D framework constructed from Cu6S6 and Cu6I6 Cu(i) clusters, notably, four alpha and two beta type N&z.dbd; C-SH parts are involved in the formation of the Cu6S6 cluster, however, only mpymt- ligands containing alpha type N&z.dbd; C-SH parts form the bridged Cu6I6 cluster. The experimental results reveal that halogen ions finely modulate the structural features of compounds 1-3. The fluorescent properties of compounds 1-3 in the solid state and in various solvent emulsions were investigated in detail, the results of which indicate that compounds 1-3 are all highly sensitive naked eye colorimetric sensors for NB, 2-NT and Fe3+ (NB = nitrobenzene and 2-NT = 2-nitrotoluene).