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The 6-substituted 3-bromo-5-iodo-2(2H)-pyranones 11, prepared by iodolactonization of the corresponding 5-substituted (E)-2-bromo-2-en-4-ynoic acids 10, were used as precursors to 5,6-disubstituted 3-methyl-2(2H)-pyranones 8 and 6-substituted 3-methyl-2(2H)-pyranones 7. The synthesis of compounds 8 involved two consecutive Stille-type reactions, whereas the approach followed to prepare compounds 7 consisted of the selective reduction of the dihalogen derivatives 11 to the corresponding 6-substituted 3-bromo-2(2H)-pyranones 12, followed by a Pd/Cu-catalysed reaction with tetramethyltin. However, this synthetic approach to compounds 7 proved to be unsuitable for preparing stereoiso-

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