Monosubstituted Keggin as heterogeneous catalysts for solvent-free cyanosilylation of aldehydes and ketones

Abstract

Any successful catalyst should have a dedicated synthesizing route considering their high yields, time-efficient, and do not require any highly toxic chemicals. In this regard, two nano-sized monosubstituted polyoxometalates (POMs) with the well-known Keggin structure were synthesized and characterized: (TBA)4[Zr(OH)PW11O39]·22H2O (TBA-ZrPW11) and (TBA)5[Zr(OH)SiW11O39]·17H2O (TBA-ZrSiW11) (TBA+: tetrabutylammonium). Thus, the catalytic activities of both catalysts were tested in the cyanosilylation reaction without any solvents of various aldehydes and ketones with trimethylsilyl cyanide (TMSCN) over two heterogeneous catalysts. Finally, the recyclability and heterogeneity of these POM-based catalysts were also checked, showing that they remain active at least after three recycling procedures.