Synthesis of alpha,beta-unsaturated 4,5-disubstituted gamma-lactones via ring-closing metathesis catalyzed by the first-generation Grubbs' catalyst.
[reaction: see text] 4-Methyl-5-alkyl-2(5H)-furanones have been prepared by ruthenium-catalyzed ring-closing metathesis of the suitable methallyl acrylates. Despite the electron deficiency of the conjugated double bond and of the gem-disubstitution of the allylic alkene moiety in the starting acrylates, the first-generation Grubbs' catalyst I proved to be an effective promoter for the ring closure, affording the expected butenolides in good to high yields.
Bassetti
Mauro
M
Istituto CNR di Metodologie Chimiche, Sezione Meccanismi di Reazione, Dipartimento di Chimica, Università degli Studi "La Sapienza", P.le Aldo Moro 5, 00185 Roma, Italy. mauro.bassetti@uniroma1.it
D'Annibale
Andrea
A
Fanfoni
Alessia
A
Minissi
Franco
F
D000475:Alkenes / Q000138:chemical synthesis; D002384:Catalysis; D003500:Cyclization; D007783:Lactones / Q000138:chemical synthesis*; D015394:Molecular Structure; D012428:Ruthenium / Q000737:chemistry*; D013237:Stereoisomerism
D000475:Alkenes; D007783:Lactones; D012428:Ruthenium