Francisco Farin˜a, M. Maestro, M. Martín
1987
Citations
0
Influential Citations
15
Citations
Journal
Tetrahedron
Abstract
Abstract The reaction of 3-bromo-5-methoxyfuran-2(5H)-onel with the stabilized carbanions derived from 2a–d, in a solid-liquid two-phase system in the presence of potassium carbonate and tetrabutylammonium bromide, affords the cyclopropane lactones 5a–d. With the ambident anions generated from 2e and 2f, the fused heterocyclic compounds 10 and 11, respectively, are obtained. The reaction of methyl 2-bromo-4,4-dimethoxy-2-butenoates (7, 8) with 2b–f, under similar conditions, gives rise to mixtures of the functionalized cyclopropanes 12b–f and 13b–f as mixtures of diastereoisomers; dihydrofurans 14 and 15 are also formed as minor components using ethyl acetoacetate (2f) as nucleophile.