Several a,fl-unsaturated esters containing also isolated olefins or other functionalities subject to saturation were selectively reduced to the corresponding saturated esters by magnesium in methanol. During a total synthesis of pentalenene sesquiterpenes a requirement arose for the selective saturation of the acrylate moiety in l.* Review of the literature3 at the time revealed a lack of reliable methods for carrying out selective transformations of this type, although several papers reported reductions of acrylonitriles4 and acrylamides5 with magnesium in methanol This method proved applicable in the case of selective formation of triquinane 2. Surprisingly, the above two reports and a patent6 were the only instances of such reductions. During the completion of this work, several papers appeared describing reductions of acrylates with silicon hydrides and catalytic amounts of transition metal carbonyls,' low valent titanium/LiA1H4 systems, 8 and Zn-NiC12 under ultrasound radiation. 9 Only one example of selective saturation of acrylate in the presence of an olefin was reported.8