Premium
Transition‐Metal‐Mediated Cleavage of Fluoro‐Silanes under Mild Conditions
Author(s) -
Kameo Hajime,
Kawamoto Tatsuya,
Sakaki Shigeyoshi,
Bourissou Didier,
Nakazawa Hiroshi
Publication year - 2016
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201504455
Subject(s) - silanes , hypervalent molecule , chemistry , iridium , silylation , bond cleavage , hydride , metathesis , cleavage (geology) , transition metal , medicinal chemistry , rhodium , metal , silicon , salt metathesis reaction , crystallography , catalysis , photochemistry , stereochemistry , silane , organic chemistry , polymerization , materials science , polymer , reagent , fracture (geology) , composite material
Si−F bond cleavage of fluoro‐silanes was achieved by transition‐metal complexes under mild and neutral conditions. The Iridium‐hydride complex [Ir(H)(CO)(PPh 3 ) 3 ] was found to readily break the Si−F bond of the diphosphine‐ difluorosilane {( o ‐Ph 2 P)C 6 H 4 } 2 Si(F) 2 to afford a silyl complex [{[ o ‐( i Ph 2 P)C 6 H 4 ] 2 (F)Si}Ir(CO)(PPh 3 )] and HF. Density functional theory calculations disclose a reaction mechanism in which a hypervalent silicon species with a dative Ir→Si interaction plays a crucial role. The Ir→Si interaction changes the character of the H on the Ir from hydridic to protic, and makes the F on Si more anionic, leading to the formation of H δ+ ⋅⋅⋅F δ− interaction. Then the Si−F and Ir−H bonds are readily broken to afford the silyl complex and HF through σ‐bond metathesis. Furthermore, the analogous rhodium complex [Rh(H)(CO)(PPh 3 ) 3 ] was found to promote the cleavage of the Si−F bond of the triphosphine‐monofluorosilane {( o ‐Ph 2 P)C 6 H 4 } 3 Si(F) even at ambient temperature.