Intermediate and process for producing fluorinated carboxylic acid derivative from the same

A 2-fluoro-2-(3-oxocyclopentyl)acetate derivative represented by the formula (1):

• 11
• (wherein R1 is a C1-10 alkyl group, a C3-8 cycloalkyl group, a C3-8 cycloalkyl C1-6 alkyl group, an aryl group, an aryl C1-6 alkyl group, a C1-6 alkoxy C1-6 alkyl group, a C1-6 hydroxyalkyl group, a C1-6 alkylthio C1-6 alkyl group, a C1-6 mercaptoalkyl group, a tetrahydrofuranyl group, or a tetrahydropyranyl group;
• and X1 is a chlorine atom, a bromine atom, or an iodine atom).