Synthesis and chemistry of 2,2-disubstituted 1-alkenylphosphonic derivatives

Abstract

The reaction of 2-methyl-1-pentene with phosphorus pentachloride gave invariably a mixture of products which could not be isomerised to produce single compounds. Similarly, five compounds were obtained following the esterification reaction of the above-mentioned mixture. Base-catalysed phosphonate isomerisation of the mixtures of the alkenyl diesters, as well as attempted standard chromatographic methods, failed to give single compounds. Pureαβ- and β¥-unsaturated phosphonates have been obtained in high yields by independent, unambiguous routes. Prototropic equilibrium studies on the pure alkenyl phosphonates were carried out and hyperconjugation effects operating in such systems were discussed. A gas chromatographic study of the alkenylphosphonate mixtures and of the pure compounds gave chromatographic data previously unreported for compounds of this type.