title: Reaction of trimethylsilylacetylenes with antimony pentafluoride under matrix isolation conditions: experimental and computational study.
abstract: Reaction of trimethylsilylacetylenes Me(3)SiC≡CR with SbF(5) in the solid state was investigated using matrix isolation infrared spectroscopy and quantum-mechanical calculations. Two reaction pathways were detected. Replacement of the trimethylsilyl group with SbF(4) produces neutral antimony acetylides F(4)SbC≡CR. Acetylenic bond protonation produces silyl cation 6-R, fully bridged for R = H and SiMe(3). High total charges on the bridging SiMe(3) group and low Me(3)Si-C bond orders to acetylenic moiety, both calculated at the MP4(SDQ)/6-311G(d,p) level of theory, indicate high silyl cation character of these species.
authors.affiliation: Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, 10000 Zagreb, Croatia.
authors.forename: Helena
authors.initials: H
authors.lastname: Cicak
authors.forename: Hrvoj
authors.initials: H
authors.lastname: Vancik
authors.forename: Zlatko
authors.initials: Z
authors.lastname: Mihalić
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D000965:Antimony / Q000737:chemistry*; D005459:Fluorides / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D011789:Quantum Theory; D014297:Trimethylsilyl Compounds / Q000737:chemistry*
chemical_list: D000480:Alkynes; D009942:Organometallic Compounds; D014297:Trimethylsilyl Compounds; C529140:antimony pentafluoride; D000965:Antimony; D005459:Fluorides