A valuable variation of the Knoevenagel-Doebner reaction
for the efficient synthesis of cinnamic esters is described. This reaction
provides cinnamic esters in a single step from gem-dibromomethyl
aromatics, which otherwise require the hydrolytic conversion of gem-dibromides into aldehydes, and demonstrates
the use of an alternative reagent for noncommercial and expensive
aldehydes. Further, the reaction of gem-dibromomethyl
aromatics with malonic acid and di-tert-butyl
dicarbonate for the one-pot synthesis of tert-butyl
cinnamates is also described.
Knoevenagel-Doebner reaction -
tert-butyl cinnamates -
gem-dibromomethyl aromatics - di-tert-butyl dicarbonate - hydrolytic