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We describe herein a CrCl
2-pro
moted cyclopropanation of
![](/i<font color=)
mages/gifchars/alpha.gif" BORDER=0>,
![](/i<font color=)
mages/gifchars/beta2.gif" BORDER=0 ALIGN="
middle">-unsaturated a
mides. This reaction can be carried out on (
E)- or (
Z)-
![](/i<font color=)
mages/gifchars/alpha.gif" BORDER=0>,
![](/i<font color=)
mages/gifchars/beta2.gif" BORDER=0 ALIGN="
middle">-ena
midesin which the C-C double bond is di-, tri-, or tetrasubstituted. In all cases the process is co
mpletely stereospecific and only a single diastereoiso
meris obtained. In addition, cyclopropyl ketones were readily prepared by reaction of the cyclopropanecarboxa
mides (derived fro
m morpholine)obtained with a range of organolithiu
m co
mpounds. A
mechanis
m has been proposed to explain the cyclopropanation reaction.