101054-92-6Relevant articles and documents
Deamination Reactions, 43 - The Effect of Trifluoromethyl Groups on the Reactivity of Aliphatic Diazonium Ions and Carbocations
Gassen, Karl-Rudolf,Kirmse, Wolfgang
, p. 2233 - 2248 (2007/10/02)
Various trifluoroalkanamines (9, 26, 35, 38, 45, 56, and 67) have been prepared and diazotized (water, pH 3.5) to probe the effect of trifluoromethyl groups on the reactivity of aliphatic diazonium ions.The product distributions reveal that α-CF3 groups enhance inverting displacement and enforce rearrangement (hydride shifts) separating the positive charge from CF3.Migrations of the positive charge from the β- to the γ-position are less strongly promoted than those from α to β.Enhancement factors of ca. 15 (α -> β) and 4 (β -> γ) may be derived by comparison with analogous alkanediazonium ions.The positive charge does not migrate in the reverse direction (β -> α) except for minor amounts of a pinacolic rearrangement (68 -> 7).A migration of the positive charge from γ to β has been detected with 36 but a tenfold decrease as compared to the analogous butanediazonium ion 37 is indicated.All observations are reasonably explained in terms of the relative stabilities of the intermediate trifluoroalkyl cations.