HIGHLY STEREOSELECTIVE NUCLEOPHILIC-ADDITION TO CYCLOPROPYL CARBONYLS- THE FACIAL SELECTIVITY IN THE CYCLOPROPYL KETONES IS OPPOSITE TO THAT IN THE CORRESPONDING ALDEHYDE

Nucleophilic addition reaction of Grignard reagents to cyclopropylcarb aldehyde 4 proceeded highly selectively from the si-face to afford 5 i n high yield. Although hydride reduction of the corresponding ketone 7 with L-Selectride(R) also proceeded highly diastereoselectively, the facial selectivity was reversed to give the re-Face addition product 5 . On the other hand, reduction of 7 with DIBAL-H afforded si-face addi tion product 6 in high yield. The result suggested that these nucleoph ilic addition reaction proceeded via either the bisected s-trans or s- cis conformation of the cyclopropane derivatives.