The catalytic activity of theMFe2O4 spinel (M ¼ Mn, Co, Cu, Ni, Zn) was investigated for the oxidation of benzylic alcohols to respective carbonyls using tert-butyl hydroperoxide (TBHP) as an oxidant. The combination of CoFe2O4/TBHP in a dimethyl sulfoxide (DMSO) catalytic system was found to be most efficient for this catalytic conversion. A CoFe2O4 catalyst is magnetically separable and could be reusedwith no considerable loss in catalytic activity as proved for 5 consecutive cycles.

A simple and environmentally benign synthesis of 2-amino-4H-chromene is described using hydrotalcite as a solid base catalyst in aqueous medium. The catalysts were prepared by a co-precipitation method and well characterized by various techniques such as XRD, FT-IR, SEM and the basicity was found using the phenol adsorption method. The reusability of the catalyst, use of water as a green solvent and easy isolation of the product along with good yields make the present protocol sustainable and advantageous compared to conventional methods.
DOI:10.1039/C3CY20856G

Various cyclic systems containing active methylene sites are converted to ketones with a high level of selectivity under the optimized conditions