83571-52-2Relevant academic research and scientific papers
KINETICS OF NUCLEOPHILIC ATTACK ON COORDINATED ORGANIC MOIETIES. XX. NOVEL ANCHIMERIC ASSISTANCE IN THE ADDITION OF ARYL PHOSPHINES TO +
Atton, J. G.,Kane-Maguire, L. A. P.
, p. C43 - C45 (1982)
Kinetic studies in acetone solvent of the addition of triarylphosphines, (XC6H4)3P, to the dienyl ring of + (I) reveal the following rate variation with X: 2-MeO > 4-MeO > 4-Me > H >> 2-Me (relative rates 90/9/4/1/10-3).The unexpectedly rapid reaction with (2-MeOC6H4)3P is rationalised in terms of stabilization of the transition state via an anchimeric effect involving overlap between the filled 2p orbital of the 2-MeO oxygen and the empty phosphorus 3d orbital.This anchimeric effect, quantified by the k(2-MeO)/k(H) ratio of 91, is considerably larger than that previously observed for addition of arylphosphines to benzyl chloride, suggesting a greater degree of phosphorus-carbon bond formation in the transition state for attack on (I).
