Dr. Misbahu Ladan Mohammed is currently working as a Senior Lecturer in the Department of Pure and Applied Chemistry, Usmanu Danfodiyo University, Sokoto, Nigeria. He obtained his PhD in Chemical Engineering from London South Bank University (LSBU), UK. He won the first prize at the Institution of Chemical Engineers (IChemE), UK research event (2012) at Air Products, Basingstoke, UK. Before joining LSBU, Dr. Mohammed received his MSc with Distinction in Advanced Process Engineering from Loughborough University, UK and a B.Sc. in Applied Chemistry from Usmanu Danfodiyo University, Sokoto, Nigeria.
Alkene epoxidation is a very useful reaction in organic syntheses as the resultant epoxides are highly reactive compounds that are used as raw materials or intermediates for the production of commercially important products, e.g. flavours, fragrances, paints and pharmaceuticals. In this work, a polystyrene 2-(aminomethyl)pyridine supported molybdenum(VI) complex (Ps.AMP.Mo) has been prepared, characterised and used as catalyst for epoxidation of 4-vinyl-1-cyclohexene (4-VCH) using tert-butyl hydroperoxide (TBHP) as an oxidant. The efficacy of Ps.AMP.Mo catalyst has been assessed for continuous epoxidation of 4-vinyl-1-cyclohexne with TBHP as an oxidant using a FlowSyn reactor by studying the effect of reaction temperature, feed molar ratio of alkene to TBHP and feed flow rate on the conversion of TBHP and the yield of 4-vinyl-1-cyclohexane 1,2-epoxide. The catalyst was found to be active and selective for continuous epoxidation of the substrate using TBHP as an oxidant. This process is considered to be clean as (i) it employs efficient and selective heterogeneous catalyst, (ii) it is solvent less, (iii) it uses a benign oxidant (TBHP), which becomes active only on contact with the catalyst and (v) it is atom efficient and the alcohol by-product itself is an important chemical feedstock. The continuous epoxidation in a FlowSyn reactor has shown considerable time savings, high reproducibility and selectivity along with remarkable improvement in catalyst stability compared with the reactions carried out in a batch reactor.