2-bromo-4-methyl-2H-furan-5-one 、 (3Z,3aS,6aS)-3-(羟基亚甲基)-3,3A,4,6A-四氢-2H-环戊二烯并[b]呋喃-2-酮 生成 (3E,3aS,6aS)-3-[[(2R)-4-methyl-5-oxo-2H-furan-2-yl]oxymethylidene]-4,6a-dihydro-3aH-cyclopenta[b]furan-2-one 、
2H-Cyclopenta(b)furan-2-one, 3-((((2S)-2,5-dihydro-4-methyl-5-oxo-2-furanyl)oxy)methylene)-3,3a,4,6a-tetrahydro-, (3E,3aS,6aS)-