Addition reactions O 0060 Solvent-Free Thia-Michael Addition Reactions Using 3-[Bis(alkylthio)methylene]pentane-2,4-diones as Efficient and Odorless ThiolEquivalents. -Facile acid-promoted thia-Michael addition reactions to various chalcone, aliphatic conjugated ketones and conjugated esters using α-oxo ketene-S,S-acetals (I) as practical, efficient and odorless thiol equivalents are described. -(LIN, C.; ZHAO, X.-L.; OUYANG, Y.; YU, H.-F.; DONG*, D.-W.; Chin.