Kinetic studies of Lewis acidity. Part I. Anionotropic rearrangement of 1-phenylprop-2-en-1-ol catalysed by aluminium(III), antimony(III), antimony(V), boron(III), gallium(III), phosphorus(III), phosphorus(V), phosphoryl, tin(IV), titanium(IV), and zinc(II) chlorides

Abstract

In sulpholan solution 1-phenylprop-2-en-1-ol undergoes an anionotropic rearrangement to cinnamyl alcohol in the presence of metal and non-metal chloride Lewis acids. The rates of rearrangement are first order with respect to the alcohol, and are directly proportional to the concentration of the catalyst. A general mechanism is proposed. Relative rate constants for the rearrangement at 35° are: GaCl₃ 350, SnCl₄ 74, PCl₅ 38, SbCl₅ 26, POCl₃ 21, TiCl₄ 9·3, AICI₃ 6·5, BCl₃ 3·9, PCl₃ 2·8, HCl 1·0, SbCl₃ 4·1 × 10^–2, and ZnCl₂ 9·1 × 10^–6.