KINETICS AND MECHANISM OF AMINOLYSIS OF PROPARGYL AND 1-METHYL-PROPARGYL ARENESULPHONATES

Article abstract of DOI:10.1002/poc.610071107

Kinetic studies were carried out on the aminolysis of propargyl and 1-methylpropargyl arenesulphonates in acetonitrile at 45.0 deg C.The cross-interaction constants, ρ_xz and β_xz, are similar to, but smaller than, those for the S_N2 processes at other primary and secondary carbon centers.Compared with the allyl series, the smaller magnitude of ρ_xz and β_xz reflects a looser transition state, which in turn leads to a lower rate despite the greater Taft's ?^* value and the lower intrinsic (ΔE₀^<*>) and thermodynamic barriers (ΔE⁰).