Reactivities of cis ‐ and trans ‐buten‐2‐yl free radicals in presence of D 2 S. I. Relative values of rate constants

Cis ‐ and trans ‐buten‐2‐yl free radicals are shown to react with D 2 S in metathetical steps:Relative formation rates of monodeuteriated butenes in D 2 S – 2 – C 4 H 8 mixtures were measured at low extent of reaction in the experimental range: 20–200 torr 2 – C 4 H 8 , 0–41‐torr D 2 S and 717–817 K. In these pressure and temperature ranges, the fractional rate constant values k c / k c′ / k t / k t′ remain practically constant and equal to: 0.36/0.17/0.32/0.15. It is concluded from these data that cis ‐buten‐2‐yl free radicals are a little more reactive than their trans ‐isomers and that the mesomeric form CH 3 CH:CHCH 2 is about twice as reactive as CH 3 ĊHCH:CH 2 .