Fexo Chloro or Methyl 4-(4-chloro-1-oxobutyl)-alfa,alfa-dimethylbenzene acetate is a pharmaceutical intermediate primarily used in the synthesis of Fexofenadine, a second-generation antihistamine. It plays a critical role in the manufacture of non-drowsy allergy medications. The compound features a chlorobutyryl functional group that allows for its efficient transformation into Fexofenadine API during pharmaceutical production. Methyl 2-(4-(4-chlorobutanoyl)phenyl)-2-methylpropanoate is an organic chemical intermediate utilized for the synthesis of pharmaceutical and agrochemical compounds. It has properties that make it an ideal building block for creating active ingredients in various chemical formulations. Methyl 2-(4-(4-chlorobutanoyl)phenyl)-2-methylpropanoate is a descriptive chemical name.