Inexpensive bulk Ni–Sn alloy-based catalysts demonstrated a unique catalytic property in the selective conversion of C5-furan compounds (e.g., furfuraldehyde (FFald), furfuryl alcohol (FFalc), and 2-methylfuran (2-MTF)) in an ethanol/H₂O solvent mixture and selectively produced 1,4-pentanediol (1,4-PeD) in a one-pot reaction. The synergistic actions between the bulk Ni–Sn alloy catalyst, hydrogen gas, and the hydroxylated H₂O or ethanol/H₂O solvents are believed to play a prominent role in the catalytic reactions. Bulk Ni–Sn alloy catalysts that consisted of Ni₃Sn or Ni₃Sn₂ alloy phases allowed an outstanding yield of 1,4-PeD up to 92% (from FFald), 67% (from FFalc), and 48% (from 2-MTF) in ethanol/H₂O (1.5 : 2.0 volume ratio) at 433 K, 3.0 MPa H₂ and 12 h. As the reaction temperature increased to 453 K, the yield of 1,4-PeD slightly decreased to 87% (from FFald), whereas it slightly increased to 71% (from FFalc). The bulk Ni–Sn alloy catalysts were reusable without any significant loss of selectivity.