Green and eco-friendly synthesis of α-hydroxyphosphonates as antioxidant and antimicrobial agents

• Synthesis of novel α -hydroxyphosphonates under r.t. and neat conditions. • Nano NiO used as a reusable and heterogeneous catalyst, with 90–95% yields. • Compounds with electron rich groups showed high antioxidant activity. • Compounds having halo and nitro groups showed good antimicrobial activities • All the designed compounds have shown significant drug-like characteristics . An efficient, fast and eco-friendly synthesis of α-hydroxyphosphonates are synthesized via neat reaction of various structurally diverse aldehydes and diethyl phosphite under ambient temperature and solvent free conditions using nano NiO as catalyst. Use of nano NiO as an inexpensive catalyst makes the protocol more economical. Mild reaction conditions and simple work-up procedure are the added advantages of the present protocol. The bio-assay revealed that the title compounds exhibited good antioxidant and antimicrobial activities. Especially compounds 3a, 3e, 3h and 3i showed high activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO) and hydrogen peroxide (H 2 O 2 ) methods whereas the compounds 3b, 3c and 3f showed good antimicrobial results compared than that of the standard drugs.