Unsaturated carbonyls can be prepared in the laboratory in an aldol reaction and in the Perkin reaction.
2.
Rxn of " p "-fluorobenzyl chloride ( "'1 "') with the anion of diethylmethyl malonate ( "'2 "') gives intermediate diester ( "'3 "'), saponification of which and subsequent decarboxylation leads to "'4 "'. { Alternatively it can be formed by Perkin reaction between p-fluorobenzaldehyde and propionic anhydride in the presence of NaOAc, followed by catalytic hydrogenation of the olefinic bond using a palladium on carbon catalyst .}
3.
William Perkin continued active research in organic chemistry for the rest of his life : he discovered and marketed other synthetic dyes, including " Britannia Violet " and " Perkin's Green "; he discovered ways to make coumarin, one of the first synthetic perfume raw materials, and cinnamic acid . ( The reaction used to make the latter became known as the Perkin reaction . ) Local lore has it that the colour of the nearby Grand Union Canal changed from week to week depending on the activity at Perkin's Greenford dyeworks.