3-[3-(2,2-dimethylpropoxy)-4-methoxyphenyl]-4,4-diethoxy-2-ethoxycarbonylbutyric acid ethyl ester 、
3-(3,4-dimethoxyphenyl)-4,4-diethoxy-2-ethoxycarbonyl butyric acid ethyl ester 以to obtain a light yellow solid of the above-referenced compound via 3-[3-(2,2-dimethylpropoxy)-4-methoxyphenyl]-4,4-diethoxybutyric acid (yield 68.7%)的产率得到3-[3-(2,2-dimethylpropoxy)-4-methoxyphenyl]-4,4-diethoxybutyric acid