461-24-5

Treatment of 2,2,2-trifluoroethyl chloride (HCFC-133a) with alcohols (phenols) and aqueous KOH in autoclave at 240-280 C gives the corresponding 2,2,2-trifluoroethyl (2-chloro-1,1-difluoroethyl) ethers in good yields.

The metal ions Fe(2+), Zn(2+) and Cu(2+) bring about the rapid decomposition of 1-aryl-3-alkyltriazenes to the corresponding anilines.For Fe(2+), a linear dependence of the pseudo-first-order rate constant, k0, on was observed, while for Zn(2+) and Cu(2+) plots of k0 versus were curved and indicative of complex formation.For Fe(2+), second-order rate constants k2Fe(2+) for substituted 1-aryl-3-methyltriazenes follow a Hammett relationship giving rise to a ρ value of -3.0.For Zn(2+) and Cu(2+), the data were analysed in terms of an equilibrium konstant, KM(2+), for the dissociation of a metal-ion-triazene complex and the first-order rate constant, for the collapse of this complex to products, k2M(2+).Hammett ρ values of 1.0 for both KZn(2+) and KCu(2+) are found, and the corresponding ρ values for k2Zn(2+) and k2Cu(2+) are -1.3 and -1.9.There is reasonable correlation between the Taft Eg parameter for the alkyl group and KCu(2+), giving a δ value of -1.6.The dependence of k2Cu(2+) on the alkyl group is not simple: k2Cu(2+) decreases in the order Pr > Et * PhCH2 ca. 4-MeOC6H4CH2 > CD3 ca.Me.The reactions catalysed by Cu(2+) are inhibited by added nucleophiles e.g.Br(1-) and N-methylimidazole. A mechanism is proposed in which the triazene complexes to the metal ion via the N(1) nitrogen atom of the E-cis conformer, then undergoes a fast proton transfer to form a complex involving the unconjugated tautomer which subsequently decomposes via unimolecular scission of the N(2)-N(3) bond to form an alkyldiazonium ion and an aniline-metal complex.The observed products then arise from rapid solvolysis of the metal-aniline complex and the alkyl diazonium ion.