4-Ethoxy­carbonyl-3-furoic acid

The title compound, (I), represents the first example of a crystal structure of a mono-ester of furoic acid. Previous related crystal structures observed in the Cambridge Structural Database (CSD, Version 5.26; Allen, 2002) include the cyclohexane (CSD refcode CIHNIQ; Baldwin et al., 1997) and methyl (CSD refcode FURCAM; Okada et al., 1971) diesters, and the diacid (CSD refcode FURDCB and derivatives), although there has been some discussion as to the correct space group of this compound (Williams & Rundle, 1964; Semmingsen et al., 1986).