The Preparation of a Residue‐free, Alumina‐supported Gold Catalyst by Decomposition of an Azido‐Gold(III) Complex and an Evaluation of the Effectiveness of the Catalyst for the Hydrogenation of Propyne

A 1 % w/w alumina‐supported gold catalyst is described that is prepared from the impregnation of alumina with a solution of ammonium tetraazidoaurate(III), NH 4 [Au(N 3 ) 4 ]. Decomposition of the azide precursor leads to a residue‐free catalyst comprised of well‐dispersed gold particles. This novel material is tested for propyne hydrogenation using pulse‐flow techniques and displays 100 % selectivity to the partial hydrogenation product, propene, albeit in the presence of a large retention of hydrocarbon by the catalyst. The latter characteristic is associated with a support‐mediated deactivation pathway. Comparing catalytic performance with a 1.45 % w/w Au/TiO 2 reference catalyst indicates that chlorine‐free precursor compounds are not required to enhance catalytic activity for this particular reaction.