SALT EFFECTS IN THE MERCURATION OF UNSATURATED-COMPOUNDS - KINETIC EVIDENCE FOR THE FORMATION OF ION-PAIRS AND A SOLVATED ION

The kinetics of mercuration of bornylene and cyclohexene in different solvents in the presence of NaOAc and LiClO4 has been investigated. Ad dition of NaOAc sharply decreases the rate of addition reactions of me rcuric acetate to bornylene and cyclohexene in alcohols; the main dire ction of the mercuration of bornylene is the formation of acetoxy-addu cts, and the yield of solvo-adducts decreases from 76 % in the absence of NaOAc, to 19 % in the presence of the salt (4.10(-3) mol L(-1)). A reaction scheme involving the participation of intermediate ion pairs and a solvated mercurinium ion is suggested and confirmed by a steady -state concentration method. The influence of NaOAc on the rate of the reaction and on product formation is realized through the common ion effect.