Aurophilic towards H‐Bonding Interactions in Phosphine‐pyrazolato‐gold(I) Complexes: Luminescence Studies and Crystal Structure of {3,5‐Bis[4‐(octyloxy)phenyl]‐1H‐pyrazolato‐κN1}(triphenylphosphine)gold{3,5‐Bis[4‐(octyloxy)phenyl]‐1H‐pyrazole} ([Au(pz)(PPh3)]⋅(Hpz))

Abstract Compounds [{Au(pz )(PPh3)}2] (pz =3,5‐disubstituted pyrazolato; R=BuOC6H4 (bp), 1; R=C8H17OC6H4 (op), 2; R=C6H13OC6H4 (hp), 3) were easily obtained by reaction of [Au(NO3)(PPh3)] and the corresponding pyrazolato ligand. They exhibit similar NMR patterns, their ESI‐MS or FAB‐MS data being in agreement with a monomeric molecular formulation [Au(pz )(PPh3)]. By contrast, 1 crystallizes as the dimer [{Au(pz )(PPh3)}2] and exhibits aurophilic Au ⋅⋅⋅Au contacts, while crystallization of 2 in CH2Cl2/hexane gives rise to compound 4, [Au(pz )(PPh3)]⋅(Hpz ). The X‐ray structure of 4 was solved, showing a H‐bond interaction between the monomer of 2 and Hpz . Reactions between [{Au(pz )(PPh3)}2] and their corresponding 1H‐pyrazole (Hpz ) were also explored. Compounds 1–3 exhibit luminescence in the solid state. Their emission spectra are reported and analyzed.