Reaction of disulphides with cyclic phosphoramidites

Abstract

It has been observed that cyclic phosphoramidites react more slowly than triphenylphosphine with diallyldisulphide and do not give a quantitative yield of monosulphide. Therefore, contrary to expectation, these reagents are unsuitable for use as chemical probes for determining the structure of sulphurvulcanised rubber. It appears that, like triphenylphosphine, the cyclic phosphoramidites react with allylic disulphides by a SNi' mechanism.