ethyl 4-(2,3-dihydro-6-methyl-4-oxo-5-phenyl-4H-1,3-oxazin-3-yl)-4-methyl-3-oxo-pentanoate 、
lithium;hydride 、
顺式-1,4-二氯-2-丁烯 在
乙醚 、 Brine 、
magnesium sulfate 、
ethyl acetate n-hexane 、
ethyl 1-[2-(2,3-dihydro-6-methyl-4-oxo-5-phenyl-4H-1,3-oxazin-3-yl)-2-methylpropionyl]cyclopent-3-enylcarboxylate 作用下,
以
乙二醇二甲醚 、
六甲基磷酰三胺 为溶剂,
反应 49.0h,
以to give ethyl 1-[2-(2,3-dihydro-6-methyl-4-oxo-5-phenyl-4H-1,3-oxazin-3-yl)-2-methylpropionyl]cyclopent-3-enylcarboxylate (Compound 9, 0.62 g), NMR: 1.20(3H, t), 1.52(6H, s), 1.91(3H, s), 3.0-3.25(4H, m), 4.14 (2H, q), 5.17(2H, s), 5.56(2H, s), 7.2-7.4(5H, m)的产率得到ethyl 1-[2-(2,3-dihydro-6-methyl-4-oxo-5-phenyl-4H-1,3-oxazin-3-yl)-2-methylpropionyl]cyclopent-3-enylcarboxylate