Metal-containing zeolites, especially Sn-Beta, perform as very efficient heterogeneous catalysts in the selective oxidation of levoglucosenone, which is considered as a platform chemical for the production of highly-valuable chemicals, towards the synthesis of the optically pure γ-lactone (S)-γ-hydroxymethyl-α,β-butenolide (HBO) using H₂O₂ as an oxidizing agent. Using Sn-Beta as a catalyst, yields up to 75% of (S)-γ-hydroxymethyl-α,β-butenolide are achieved in a “one-pot” cascade reaction. When Sn-Beta is combined with an acid resin, such as Amberlyst-15, the “two-step” process allows yields up to 90%.