Synthesis of Heterogeneous Ru(II)-1,2,3-Triazole catalyst supported over SBA-15: Application to the Transfer Hydrogen reaction and unusual highly selective 1,4-disbustituted traizole formation via Multicomponent Click Reaction
In the present study we demonstrate a simple and efficient method for ligand formation and covalent anchoring to heterogeneous support via click reaction. The complex tris(triphenylphosphine)ruthenium(II) dichloride [RuCl2(PPh3)3] anchored over the click modified ligand of SBA-15, forms a new highly efficient heterogeneous SBA-15-Tz-Ru(II)TPP catalyst. Solid state 13C, 29Si, & 31P CP-MAS NMR spectra provide evidence for the formation of the heterogeneous catalyst. SBA-15-Tz-Ru(II)TPP catalyst was screened for the multi component click cycloaddition reaction in water medium as green solvent exhibited unusual and excellent selectivity for the formation of 1,4-disubstituted triazole product under mild reaction condition. In addition, SBA-15-Tz-Ru(II)TPP catalyst also catalyzed the hydrogen transfer reaction of various carbonyl compounds with excellent catalytic activity to give the corresponding alcohols. The heterogeneous catalyst can be recycled and reused several times (five) without the loss in reactivity.