Pseudoesters and derivatives. XXIII Reaction of 3-bromo-5-methoxyfuran-2(5)-one with nucleophiles. Formation of cyclopropane derivatives
1986; Elsevier BV; Volume: 42; Issue: 13 Linguagem: Inglês
10.1016/s0040-4020(01)87341-5
ISSN1464-5416
AutoresF. FARINA, M. Maestro, Michel Martin, M. V. MARTÍN, Félix Sánchez, M. Luisa Soria,
Tópico(s)Ferrocene Chemistry and Applications
ResumoThe reactions of 3-bromo-5-methoxyfuran-2 (5 H)-one (1) with nucleophiles in acetonitrile, in the presence of potassium carbonate and tetrabutylammonium bromide as a catalyst, are reported. The bromofuranone 1 reacts, with several carbon and oxygen nucleophiles to give the cyclopropane bis-lactones 7, 8, 11 or 12. When 1 is reacted with diethylamine or propane-2-thiol in a 2:1 ratio, similar cyclopropane bis-lactones 16 or 21, respectively, are formed. This behaviour is explained on the basis of a mechanism involving a double Michael addition, followed by ring closure via internal nucleophilic substitution of the halogen.
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