For a@-unsaturated acid chlorides in general, the yield of water-soluble adduct (Table 2) can be correlated with the electronic effects (inductive, conjugative, or hyperconjugative) exerted by a-and p-substituents, both in the transition state and in one of the products (ap- unsaturated ester) of the reaction. For example, stabilisation of the ap-unsaturated form, by conjugative electron displacements of the types shown, result in exclusive formation of the ...