Sekundäre Wasserstoff‐Isotopeneffekte bei der Nitrierung von Toluol

The isomer ratio in the mono‐nitration of toluene and α‐d 3 ‐toluene has been measured by gas chromatographic separation. The percentage of o‐ and p ‐nitrotoluene is not influenced significantly by the isotopic substitution in the methyl group; there is, however, a difference in the formation of the m ‐isomer, demonstrating an inverse secondary isotope effect ( k H / k D = 0.94) for the substitution in m ‐position.