Estimation of the composition of nitro-aci forms of nitromethane tautomerism by refrachor (F) an old tool for a new contemporary observation

Abstract

Compounds containing methylene group (−CH₂−) and bonded directly to electron withdrawing groups such as –NO₂ and –COCH₃ etc., are called active methylene compounds. The methylene group is active and acidic. These compounds can undergo tautomerism giving acid form. The specific and simplest example is nitromethane. Nitromethane undergoes 1,3−protropy tautomerism giving rise to aciform of nitromethane (CH₃–NO₂ $\rightleftharpoons$ CH₂NO₂H). In the present work we have tried to calculate the percentage composition of the nitroform and the aciform in the tautomeric mixture of nitromethane using a seventy-five-year-old tool called the refrachor (F).