Collect. Czech. Chem. Commun. 1981, 46, 3122-3127

Tautomerism of 5-nitro-2-furylnitromethane

Iva Srokováa, Pavel Vetešníkb, Adolf Jurášekc and Jaroslav Kováčc

a Department of Textile, Celulose and Paper, Slovak Institute of Technology, 880 37 Bratislava
b Department of Organic Chemistry, Institute of Chemical Technology, 532 10 Pardubice
c Department of Organic Chemistry, Slovak Institute of Technology, 880 37 Bratislava


UV study of properties of 5-nitro-2-furylnitromethane (I) in various solvents has shown that this compound is a very strong acid (pKa 3.98) forming an ion pair in protic solvents (water, alcohols) and existing exclusively as nitro-form in aprotic solvents (tetrachloromethane, chloroform, n-hexane, diethyl ether, dioxane). Kinetic study of tautomerism in water has given experimental values of combined rate constants of parallel reactions. Thermodynamic parameters of the tautomeric transformations have been calculated from temperature dependence of the rate constants.