The Diels–Alder reaction of in situ generated cyclohexa-1,3-dienes with methyl 4,4-diethoxybut-2-ynoate (1) followed by reverse Diels–Alder and hydrolysis affords substituted hydroxyphthalides in good yield.
原位产生的环己-1,3-二烯与4,4-二乙氧基丁-2-酸甲酯的Diels-Alder反应(1),然后反向Diels-Alder
水解,
水解得到的羟基
邻苯二酚收率高。