(Z)-2-diazonio-1-methoxy-2-[4-(6-methoxy-6-oxohex-4-ynoxy)carbonyl-3-methyl-1,2-oxazol-5-yl]ethenolate 在
dirhodium tetraacetate 作用下,
以
甲苯 为溶剂,
反应 5.0h,
以17%的产率得到9-Methyl-6-oxo-2,3,4,6-tetrahydro-chromeno[8,7-d]isoxazole-5,5-dicarboxylic acid dimethyl ester