An alumina-supported homonuclear macrocyclic zirconium complex for reformation of n-hexane

The homonuclear macrocyclic complex involving zirconium on both sites is prepared starting from 2,6-diformyl-4-methyl-phenol and 1,2-phenylenediamine, and is chemically bound to carbamate-modified alumina. The UV-Vis spectrum shows the presence of the metal on the catalyst surface. The TGA of the catalyst suggests that the catalyst is stable up to 250 degreesC. Reformation of n-hexane has been carried out in its presence under nitrogen atmosphere at considerably low temperature and pressure (423 K, 27 atm). We obtained a high conversion of 72% and the GC-MS of the product showed the forming of 2-methylpentane (2MP), 3-methylpentane (3MP), methylcyclopentane (MCP) and cyclohexane (CH). Experimental results reveal that there are no dehydrogenation (forming alkenes), dehydrocyclization (forming benzene or toluene), and cracking (forming C-1-C-5 compounds) reactions and a mechanism forming the products has been suggested. (C) 2004 Published by Elsevier B.V.