HF‐SbF5 catalysed isomerization of n‐butane‐1‐13C
- 1 January 1968
- journal article
- research article
- Published by Wiley in Recueil des Travaux Chimiques des Pays-Bas
- Vol. 87 (12) , 1435-1444
- https://doi.org/10.1002/recl.19680871212
Abstract
n‐Butane‐1‐13C is isomerized by “HF‐SbF5” to n‐butane‐2‐13C without intermediate or concurrent isomerization to isobutane. The rate of the13C‐scrambling reaction is only slightly lower than that of the isomerization of n‐pentane to isopentane. This result strongly supports the hypothesis that alkylcarboniumion rearrangements that involve a change in the degree of chain branching proceed via a protonated cyclopropane ring. That no isobutane is formed can be explained by the ring opening of protonated methylcyclopropane to the isobutyl structure being “slow” because it involves the formation of an (incipient) primary ion. This is not contradictory to the fact that t‐butyl ions are formed in strong acids from n‐butyl precursors under different conditions. The difference between HF‐SbF5 catalysed and aluminium halide‐hydrogen halide catalysed isomerizations of butane is discussed.Keywords
This publication has 22 references indexed in Scilit:
- HF‐SbF5 catalysed isomerization of 2‐methylpentane: Kinetics and mechanism of rearrangement and hydride‐ion transfer steps in alkylcarbonium ion reactionsRecueil des Travaux Chimiques des Pays-Bas, 1968
- PMR spectroscopic investigation of structures, stabilities, and rearrangement reactions of C4‐C7tertiary carbonium ions in HF‐SbF5Recueil des Travaux Chimiques des Pays-Bas, 1968
- Evidence for protonated cyclopropane intermediates in the deamination of 1-propylamine and mechanistic implications of protonated cyclopropanesTetrahedron, 1967
- Carbonium Ion Rearrangements. VI. Mechanism of the Rearrangement of Neopentyl CompoundsJournal of the American Chemical Society, 1964
- Concerning the Role of Protonated Cyclopropane Intermediates in Solvolytic Reactions. I. The Solvolysis of Cyclopropane in Deuteriosulfuric AcidJournal of the American Chemical Society, 1964
- Carbonium Ion Rearrangements. III.1 The Question of Primary Carbonium IonsJournal of the American Chemical Society, 1963
- Mechanism of Conversions of n-Propyl Carbonium Ion to Cyclopropane. 1,3-Hydrogen ShiftJournal of the American Chemical Society, 1962
- The Behavior of the t-Pentyl Cation as Produced in Deaminations and Halide Solvoyses1Journal of the American Chemical Society, 1961
- FORMATION OF 1,2-DIMETHYLCYCLOPROPANE IN THE DEAMINATION OF SATURATED ALIPHATIC AMINES1Journal of the American Chemical Society, 1960
- CYCLIZATION OF CARBONIUM TO CYCLOPROPANES1Journal of the American Chemical Society, 1960