Synthesis and characterization of novel transition metal complexes with L-Proline and their catalytic activity evaluation towards cyclohexane oxidation

Abstract

Some of first row transition metals [M = Mn (II), Fe (II) and Co (II)] complexed with L -proline amino acid were synthesized by thermal heating and characterized by FT-IR, UV–visible spectroscopy, XRD, SEM and TEM. The characterization data showed that the metal ions were bonded through N- and O-donor atoms of the amino acid. The metals-L-proline complexes exist in mixed particle sizes of amorphous and agglomerated nature. The prepared complexes were investigated to catalyze the liquid phase oxidation of cyclohexane in the presence of TBHP as an oxidant. Iron-proline complex was found to be an excellent catalyst with high selectivity towards K/A oil under the optimized reaction conditions.

Keywords

• L-proline
• transition metal complexes
• amino acid
• cyclohexane oxidation
• selectivity