Compounds of the formula:
wherein Y is OR¹, fluoro, chloro, methyl,
R¹, and R³ are independently selected from hydrogen and C₁-C₄ alkyl, R² is C₁-C₄ alkyl and X is fluoro, chloro or bromo, with the proviso that when Y is OH, X cannot be bromo and with the proviso that X can be fluoro only if R² is methyl.
式中的化合物:
其中 Y 是 OR¹、
氟、
氯、甲基、
R¹和 R³ 独立选自氢和 C₁-C₄ 烷基,R² 是 C₁-C₄ 烷基,X 是
氟、
氯或
溴,但当 Y 是 OH 时,X 不能是
溴,且只有当 R² 是甲基时,X 才可以是
氟。