Highly selective n-alkanes oxidation to ketones with molecular oxygen catalyzed by SBA-15 supported rhenium catalysts

A series of tricarbonyl Re(V) complexes, i.e. [Re(CO)3(κ3-PN2)] (1), [Re(CO)3Br(κ2-H2PNO)] (2), and [Re(CO)3Br(κ2-HPN-Pip)] (3), have been covalently anchored over modified SBA-15 as supported catalysts. Remarkably, high catalytic turnover numbers from 2240 to 2857 with high ketone selectivity was obtained for both C5 and C6-alkanes. Best oxidation condition was optimized by the variation of temperature, pressure, time and catalyst amount. A thermal stability test indicates that the catalysts are stable up to 200 °C and ICP shows negligible metal loss from the catalyst surface, after the 7th catalytic cycle, allowing further use.