Solutions of sulfur dioxide and N-ethyldiisopropylamine (EDIA) are able to reduce a, j3- unsaturatedy-dicarbonyl compounds (esters or ketones) into a-dicarbonyl alkanes. In contrast, monoactivated Michael acceptors, such as acrylates, give symmetrical sulfones. These processes involve the conjugate addition of HS02-, formed from a charge-transfer complex between EDIA and S02. Secondary amines are formed as byproducts. ...
