Selective gas phase isomerization of styrene oxide to phenylacetaldehyde in a steel tube reactor.

The gas phase isomerization of styrene oxide (STO) into phenylacetaldehyde (PhAD) in good yield and selectivity has been achieved using a steel tube reactor as catalyst in an efficient and environmentally friendly process. Under semi-optimized conditions (240 °C, N flow) a steel tube reactor filled with steel balls gave a selectivity of PhAD of 99% at 98% STO conversion. Use of an equivalent glass reactor as a control gave conversions of <5% under similar reaction conditions and revealed that the isomerization is catalyzed by both the steel reactor wall as well as the steel balls. The reactor is cheap to manufacture, and does not require re-activation before reuse. A possible mechanism for the reaction is proposed. [ABSTRACT FROM AUTHOR]