Controllable assembly, characterization and catalytic properties of a new Strandberg-type organophosphotungstate

• Published in: Dalton transactions : an international journal of inorganic chemistry 2016-01, Vol.45 (4), p.1631-1637
• Main Authors: Ma, Hong-Xin, Du, Jing, Zhu, Zai-Ming, Lu, Ting, Su, Fang, Zhang, Lan-Cui
• Format: Article
• Language: English
• Subjects: Catalysts; Clusters; Coordination compounds; Coordination polymers; Ethylene; Fluorescence; Three dimensional
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c5dt04412j

Using phenylphosphonic acid, simple tungstate and copper( ii ) compounds as starting materials, an organic-inorganic hybrid Strandberg-type organophosphotungstate, {[(Cu(H 2 O)(μ-bipy)) 2 (C 6 H 5 PO 3 ) 2 W 5 O 15 ]} n (bipy = 4,4′-bipyridyl) ( 1 ), was assembled successfully under hydrothermal conditions and characterized by physico-chemical and spectroscopic methods. Compound 1 represents the first example of a transition metal complex modified organophosphotungstate cluster. In the crystal structure of compound 1 , the polymeric 1-D {Cu-bipy} n chains are interconnected by [(C 6 H 5 PO 3 ) 2 W 5 O 15 ] 4− (abbreviated as {(C 6 H 5 P) 2 W 5 }) units into a 3-D framework. A hollow Keggin isopolytungstate [H 2 W 12 O 40 ] 6− ({W 12 })-Cu( ii ) coordination polymer, {[Cu(bipy) 2 ((μ-bipy)Cu(bipy)) 2 (H 2 W 12 O 40 )]·12H 2 O} n ( 2 ), was obtained at different molar ratios of the starting materials and pH. The two Cu( ii ) coordination polymers exhibit good acid-catalytic activity for the synthesis of cyclohexanone ethylene ketal. Their fluorescence properties were studied. A new Strandberg-type organophosphotungstate was assembled under hydrothermal conditions and displayed good fluorescence properties and catalytic activity.