A straightforward catalytic approach to obtain deuterated chloroform at room temperature

We report the catalytic activity for the complexes— cis ‐[RuCl 2 (dppb)(bipy)] ( A ), and [η 6 ‐( p ‐cymene)Ru (dppb)Cl]PF 6 ( B ), wherein dppb = 1,4‐bis(diphenylphosphine)butane, and bipy = 2,2′‐bipyridine—for the synthesis of CDCl 3 from CHCl 3 using D 2 O as deuterium source. H/D exchange reactions were performed using a chloroform/D 2 O, 1:2 molar ratio, vigorously stirred, at room temperature. One mole of KOH was dissolved in D 2 O fraction and catalytic complexes from 0.002 to 0.05 mmol were dissolved in chloroform. The H/D exchange reactions were monitored using 13 C nuclear magnetic resonance sequences without proton decoupling. The reaction using 0.01 mmol of compound A reached approximately 55% of H/D conversion in 1 h. In the same time, the reactions with 0.002 mmol of compound A and without catalyst show approximately 28% and 3% H/D exchange, respectively. Without the catalysts, the H/D exchange was only 12.0% in 5 h. For compound B, 55% H/D conversion was observed in 1 h, only when 0.05 mmol was used, which is much higher catalyst concentration. After the isolation of the chloroform fraction and two more addition of D 2 O, it was possible to obtain 95.0% H/D exchange in approximately 3 h, using 0.01 mmol of the compound A. Therefore, compound A is an efficient catalyst for a rapid and straightforward synthesis of CDCl 3 from CHCl 3 at room temperature and using D 2 O as deuterium source.