Concellón José M, Rodríguez-Solla Humberto, Méjica Carmen, Blanco Elena G
Departamento de Química OrgAnica e InorgAnica, Facultad de Química, Universidad de Oviedo, JuliAn Clavería 8, 33071 Oviedo, Spain.
Org Lett. 2007 Aug 2;9(16):2981-4. doi: 10.1021/ol070896d. Epub 2007 Jul 13.
We describe herein a CrCl(2)-promoted cyclopropanation of alpha,beta-unsaturated amides. This reaction can be carried out on (E)- or (Z)-alpha,beta-enamides in which the C-C double bond is di-, tri-, or tetrasubstituted. In all cases the process is completely stereospecific and only a single diastereoisomer is obtained. In addition, cyclopropyl ketones were readily prepared by reaction of the cyclopropanecarboxamides (derived from morpholine) obtained with a range of organolithium compounds. A mechanism has been proposed to explain the cyclopropanation reaction.
我们在此描述了一种CrCl(2)促进的α,β-不饱和酰胺的环丙烷化反应。该反应可在C-C双键为二取代、三取代或四取代的(E)-或(Z)-α,β-烯酰胺上进行。在所有情况下，该过程都是完全立体专一的，仅得到单一的非对映异构体。此外，通过将得到的环丙烷甲酰胺（衍生自吗啉）与一系列有机锂化合物反应，可轻松制备环丙基酮。已提出一种机理解释该环丙烷化反应。
