Cyclohexenone Derivatives : Part V. Further Studies on Alkylation of Hagemann's Ester

In continuation of previous studies, Hagemann's ester has been alkylated with a variety of alkyl halides. The products, in each case a mixture of C₃- and C₁-substituted esters, are analysed by N.M.R. spectroscopy, the ratio of the two being determined by the relative areas of the vinyl proton at C₃ and allylic proton at C₁. Contrary to previously accepted view, the C₁-alkylation of Hagemann's ester is found to be a general phenomenon and occurs to the extent of 2-51% depending on the nature of alkylatirg agent and the kind of base used.

Hagemann's ester has also been alkylated with di-, tri-, and tetra-methylene dihalides giving mainly spirocompounds as a result of 3, 3-dialkylation.