major product is due to N-alkylation, the minor product to O-alkylation. N-Alkylation is favoured by the presence of a tertiary amine in a solvent of low dielectric constant and also by a change of the α-halo sulfide substituent from chlorine to iodine. Complete selectivity can be achieved. The course of the reaction is rationalized in terms of the HSAB-principle.
                                    当α-卤代
硫化物与环境2-
嘧啶酮反应时,主要产物是由于N-烷基化,次要产物是O-烷基化。通过在低介电常数的溶剂中存在叔胺,以及通过将α-卤代
硫化物取代基从
氯变为
碘来促进N-烷基化。可以实现完全的选择性。根据H
SAB原理,反应过程是合理的。