HALOGEN REDISTRIBUTION REACTIONS BETWEEN ALKYL HALIDES AND TRIMETHYLSILYL IODIDE

Article abstract of DOI:10.1016/S0022-328X(00)87429-X

Trimethylsilyl iodide has been found to react rapidly at 50 deg C with 1-fluorooctane, 2-fluorooctane and benzyl fluoride to produce the corresponding octyl or benzyl iodides and trimethylsilyl fluoride.Also, it reacts rapidly and cleanly with t-butyl chloride or bromide to form t-butyl iodide.However, it does not react readily with the 1-octyl, 2-octyl, benzyl or allyl chlorides or bromides.We have discovered that tetra-n-butylammonium iodide catalyzes the reactions of primary alkyl chlorides or bromides with trimethylsilyl iodide, and molecular iodine catalyzes the reactions of secondary and tertiary alkyl chlorides and bromides.However, tetra-n-butylammonium iodide slows down the reactions of secondary and tertiary alkyl chlorides and bromides.Mechanistic pathways are suggested for each of the various types of halogen redistribution processes encountered.