Evaluation of homogeneous and heterogeneous catalytic strategies for the preparation of benzene-d6 with high deuterium enrichment

This study investigates homogeneous and heterogeneous catalytic strategies for the synthesis of benzene-d₆. By utilizing trifluoroacetic acid-d₁ as both the deuterium source and homogeneous acid catalyst, with an equivalent ratio of 200:1 to benzene at 110 °C for 10 days, we achieved benzene-d₆ with deuterium enrichment exceeding 99%. For heterogeneous catalysis, the catalytic efficiency of Pt/C surpassed that of Pd/C. The optimal conditions for producing benzene-d₆ with isotopic enrichment of ≥ 99.5% involve using Pt/C catalyst at 20 wt% relative to benzene, D₂O-to-benzene volumetric ratio of 34:1, and performing the reaction at 180 °C for 24 h over three consecutive runs.