Ru~(III)(OTf)SalophenCH2-NHSiO2-Fe: an efficient and magnetically recoverable catalyst for trimethylsilylation of alcohols and phenols with hexamethyldisilazane

摘要

Efficient trimethylsilylation of alcohols and phenols with hexamethyldisilazane (HMOS) catalyzed by ruthenium(III) complex of chloromethylated Salophen supported on nanomagnetic materials is reported. First, the iron nanomagnets were silica coated, functionalized with amine and then ruthenium CM-Salophen was successfully bonded to their surface. The catalyst, Ru~(III)(OTf) SalophenCH2-NHSiO2-Fe, was characterized by elemental analysis, FT-lR and UV-visible spectroscopic techniques, transmission electron microscopy and inductively coupled plasma (ICP). The Ru~(III)(OTf)SalophenCH2-NHSiO2-Fe catalyzed trimethylsilylation of primary and secondary alcohols as well as phenols, and the corresponding TMS ethers were obtained in high yields and short reaction times at room temperature. This new heterogenized trimethylsilylation catalyst is easily recovered with a magnet and showed no appreciable loss of activity even after five consecutive runs.