Phenylacetylene semihydrogenation over a palladium pyrazolate hydrogen-bonded network

[Display omitted] •The first use of a metal azolate/carboxylate (MAC) Pd-dmpzc network for transfer hydrogenation.•Semihydrogenation of phenylacetylene in water with NaBH4 as a hydrogen source.•Superior catalytic properties of Pd-dmpzc compared to other Pd precursors. The palladium azolate/carboxylate network (Pd-dmpzc) catalyses the selective hydrogenation of phenylacetylene to styrene in water. Under optimised conditions, at a Pd:NaBH4 ratio of 1:100 at 40 °C, Pd-dmpzc provided much better results than Pd(OAc)2 or PdCl2(CH3CN)2. Analysis of the recovered catalyst revealed the presence of different Pd2+ species and Pd0 NPs which contributed in the catalytic reaction.