title: Solvent-free heterogeneous catalysis for cyanosilylation in a dynamic cobalt-MOF.
abstract: The butterfly-like tetranuclear cobalt cluster based 3D MOF [Me2NH2][Co2(bptc)(μ3-OH)(H2O)2] (1) underwent a reversible thermally triggered single-crystal-to-single-crystal transformation via Co-Owater weakened intermediate 1a to produce a partly dehydrated phase [Me2NH2][Co2(bptc)(μ3-OH)(H2O)] (2), which was confirmed by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric analysis, and IR spectroscopy. During the dehydration course, the local coordination environment of one Co(2+) ion was changed from the saturated octahedron to a coordinately unsaturated square-pyramid, accompanied by a crystal color change from red to purple. Compared with pristine hydrated 1, dehydrated 2 exhibits highly efficient and recyclable catalytic activity for cyanosilylation of carbonyl compounds with a low catalyst loading of 0.1 mol% Co at room temperature under solvent-free conditions, which due to the open Co(2+) sites as catalytically activated sites played a significant role in the heterogeneous catalytic process.
authors.affiliation: Department of Chemistry & Material Science, Shanxi Normal University, Linfen 041004, P. R. China. zhangxm@dns.sxnu.edu.cn yaoruxin1974@163.com.
authors.forename: Xin
authors.initials: X
authors.lastname: Cui
authors.forename: Mei-Chen
authors.initials: MC
authors.lastname: Xu
authors.forename: Ling-Juan
authors.initials: LJ
authors.lastname: Zhang
authors.forename: Ru-Xin
authors.initials: RX
authors.lastname: Yao
authors.forename: Xian-Ming
authors.initials: XM
authors.lastname: Zhang
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D002384:Catalysis; D003035:Cobalt / Q000737:chemistry*; D018360:Crystallography, X-Ray; D003486:Cyanides / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D033362:Powder Diffraction; D014297:Trimethylsilyl Compounds / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D000447:Aldehydes; D003486:Cyanides; D009942:Organometallic Compounds; D014297:Trimethylsilyl Compounds; D003035:Cobalt; C058010:trimethylsilyl cyanide