ETHANE ELIMINATION FROM C11H24+ ISOMERS - THE EFFECT OF THE POSITION OF FORMATION OF THE NEUTRAL IN RELATION TO THE IONIC PARTNER ON THE COMPETITIVENESS OF ION NEUTRAL COMPLEX-MEDIATED ELIMINATIONS

Competition between loss of ethyl and ethane elimination through [C2H5.C9H19+] complexes is assessed as a function of the initial location of the two partners relative to each other. Ethyl loss is favored when that species originates from near the end of the chain, but ethane elimination increases steadily in relative importance as the site of cleavage is shifted towards the middle of the chain and is dominant when the ethyl is cleaved from the middle carbon. It is speculated that when the center-of-charge and the center-of-mass of the complex are substantially away from each other, individual rotation of the partners causes the ethyl group to spend relatively little time near the hydrogen atoms it can abstract, favoring simple dissociation over ethane elimination. When the two centers approximately coincide, it is supposed that the ethyl group spends much of its time near abstractable hydrogen atoms, favoring ethane elimination.