Titanium enolates from chiral N-propanoyl-1,3-thiazolidine-2-thiones containing bulky substituents at C4 turned out to be excellent platforms to get highly stereocontrolled cross-coupling reactions with acetals. Related oxazolidinethiones also afforded good results, but the corresponding oxazolidinones resulted completely unselective for such reactions, which proves that an exocyclic C=S bond is essential to attain a synthetically useful stereocontrol. (C) 2008 Elsevier Ltd. All rights reserved.