Soumi Laha

Asymmetric hydrosilylation of ketones catalyzed by magnetically recoverable and reusable copper ferrite nanoparticles.

Herein we present magnetically recoverable and reusable copper ferrite nanoparticles for asymmetric hydrosilylation of several ketones. Up to 99% enantiometric excess was obtained at room temperature using polymethylhydrosiloxane as the stoichiometric reducing agent. The copper ferrite nanoparticles were magnetically separated, and the efficiency of the catalyst remains almost unaltered up to three cycles.

An efficient copper-aluminum hydrotalcite catalyst for asymmetric hydrosilylation of ketones at room temperature

A catalyst system consisting of a copper-aluminum hydrotalcite-chiral diphosphine ligand effects asymmetric hydrosilylation of several ketones, using polymethylhydrosiloxane (PMHS) as the stoichiometric reducing agent at room temperature, with moderate-to-excellent enantioselectivities. The catalyst is recovered by simple centrifugation, and the efficiency of the catalyst remains almost unaltered even after several cycles.

Synthesis of 2-Indolyl-1-nitroalkane Derivatives Using Nanocrystalline Titanium(IV) Oxide

Abstract The catalytic Friedel–Crafts alkylation of indoles with nitroalkenes to furnish 2-indolyl-1-nitroalkane derivatives at room temperature with moderate to excellent yields is reported using nanocrystalline titanium(IV) oxide (nano-TiO2) catalyst. In all cases, a single regioisomer was obtained. After completion of the reaction, the catalyst was recovered by centrifugation and activated under a nitrogen flow for 1 h at 250°C for further reuse. The nano-TiO2 can be reused for four cycles with a slight decrease of activity under the same reaction conditions.