Aqueous extract of CAP-ash: A greener benchmark for Suzuki-Miyaura coupling reaction in palladium catalyzed ligand-free condition

•A green synthetic pathway for the construction of carbon-carbon bonds in catalytic amount of Pd(OAc)2 in aqueous extract of custard apple peels.•The reaction is performed without using any conventional inorganic or organic base.•Environmental benign condition.•An abundant agro-waste is used as alternative base in Suzuki-Miyaura reaction.•Chemical investigation of custard apple peels shown the presence K, Mg, Ca, Na, Si metal. Synthesis, molecular, spectroscopic properties, and electronic structure calculations of biphenyls derivatives have been achieved using a highly efficient catalytic amount of Pd(OAc)2 in aqueous extract of custard apple peels (CAP)-ash (AECAP) a green, highly cost-effective, operationally convenient and environmentally benign media at ambient temperature. The analytical reports showed the presence of metal oxides which are probably extracted in water produces corresponding hydroxides, which provide alkaline media in water which shows dual performance (solvent and base) for said cross-coupling transformation. The catalytic system is generated in situ based on aqueous extract and Pd(OAc)2 which requires no external base and ligand. Moreover, the study also offers insights into the frontier molecular orbitals (FMO), electronegativity, chemical potential, global electrophilicity index, ionization potential, electron affinity, chemical hardness, and softness properties of the synthesized biphenyl derivatives for understanding their stability, active sites, and biological activity using density functional theory (DFT) at the B3LYP/6–311G(d,p) level/basis. [Display omitted]