Gold nanorods (AuNRs) and silver nanoparticles (AgNPs) were fastened over single layer graphene (SLG) and successfully designated using microscopic (TEM and SEM-EDX) and spectroscopic (Raman, XRD, XPS and ICP) techniques. Salmon milt DNA stabilized the AgNPs and was also obliging in producing AuNRs. Bimetallic nanocatalyst (Au-Ag/SLG) was tremendously exerted as a versatile catalyst for hydroarylation, C-arylation and hydrophenoxylation reactions under mild and ligand-free conditions. But the mixture of monometallic nanocatalysts (Au/SLG and Ag/SLG) was unsuccessful in exposing their catalytic performance towards hydroarylation reaction. Initially the reaction conditions were optimized. 16 examples were fruitfully demonstrated for hydroarylation reaction in i-PrOH solvent with KOH. High synergistic effect was experienced with Au-Ag/SLG bimetallic nanocatalyst. Electron releasing group at the phenyl ring lead to the formation of 1,1-diphenylethylenes whereas the arenes with electron withdrawing functional group preferred hydrophenoxylation rather than hydroarylation. Consecutively C-arylation of hydroarylated products (1,1-diphenylethylenes) was achieved with iodobenzene by means of the same bimetallic nanocatalyst (Au-Ag/SLG). Leaching of metal nanoparticles during the course of the catalytic reaction was examined using heterogeneity test and ICP analysis. Reusability results confirmed the chemical stability of the proposed bimetallic Au-Ag/SLG nanocatalyst. (C) 2016 Elsevier B.V. All rights reserved.