New silver(I) complexes [Ag7(l4-Cl)(l3-Cl)2(l2-Cl)3(MPI)6] (1), and [Ag(l3-I)(BI)]n (2) [MPI = 1-(4-methoxyphenyl)-
1H-imidazole; BI = 1-Benzylimidazole] have been prepared starting with AgX (X = Cl, I) and
1-(4-methoxyphenyl)-1H-imidazole/1-Benzylimidazole. The complexes have been characterized by
elemental analysis, IR, 1H NMR, and electronic absorption spectroscopy. Molecular structure of the complexes
1 and 2 were determined crystallographically. Complex 1 has a twofold axis with Ag3 in special
position and bisecting the Ag4–Ag40 vector. It contains six 1-(4-methoxyphenyl)-1H-imidazole molecules
and seven chlorine atoms bridging the seven silver atoms. Complex 2 exists as a one-dimensional (1D)
polymeric chain of [(l3-I)Ag(l3-I)Ag] fragments bridged via the 1-Benzylimidazole ligand. The weak
argentophilic Ag Ag interaction distances in complexes 1 and 2 are 3.1014(4) Å–3.2998(15) Å, respectively.
The complexes 1 and 2, yielded silver oxide nanoparticles on pyrolysis and were characterized
by PXRD and TEM. The catalytic properties of the resulting silver oxide nanoparticles and the silver(I)
complexes have also been studied for A3-coupling of amines, alkynes and aldehydes in microwave which
gave moderate to good yields of propargylamines. Silver(I) complexes exhibit higher catalytic activity
compared to silver oxide nanoparticles. The silver oxide nanoparticles as well as silver(I) complexes could
be separated easily from the reaction mixture and reused at least four to five times without significant
loss of the catalytic activity.