Asymmetric deuteration and deuteriooligomerization of 1-pentene

Abstract

1-Pentene has been polymerized in the presence of deuterium using as catalyst precursors [Al(CH 3)-O] n and (−)-ethylenebis(4,5,6,7-tetrahydro)-( R)-1-indenylzirconium derivatives ((−)-( R)-EBTHI-ZrX 2, X = CH 3 (I); X = ( R)-1′,1″-bi-2-naphtholate (II)). The investigation of 1,2-dideuteriopentane and of the deuteriooligomers thus obtained shows that the ( Re) enantioface of the olefin is predominantly involved in the deuteration but its ( Si) enantioface in the dimerization and oligomerization. These results, which show the participation of the growing chain in the enantioface discrimination in the stereospecific polymerization of 1-pentene are discussed on the basis of a simple stereochemical model for the transition state of the olefin insertion step.