γ-heterosubstituted γ-methyl-α,β-butenolides are presented, starting mainly from C3 synthons (glyceraldehyde, glycidaldehyde, acrolein and 2,3-epoxypropyl ethers). Good general methods for the preparation of γ-hydroxymethyl-α,β-butenolide 2, several of its ether derivatives, as well as of γ-bromomethyl-α,β-butenolide 5, are given. The reactivities of these structurallysimple but highly functionalized compounds