Trionfo di_ Giulio _Cesare_  One method to synthesize substituted versions of these compounds begins with a Knoevenagel condensation between a beta di
Trionfo di_ Giulio _Cesare_  One method to synthesize substituted versions of these compounds begins with a Knoevenagel condensation between a beta dicarbonyl group and an alpha halogen ketone, and is known as the Feist-Benary synthesis. One of these with a hydroxyl side chain reacts with bromine and methanol to produce dihydropyran in the Achmatowicz reaction, while in the Paal-Knorr synthesis, a 1,4-diketone reacts with an acid catalyst to produce one of these. Changing one reactant in that same reaction can produce their sulfur and nitrogen analogues, thiophenes and pyrroles, respectively, all three of which are aromatic due to an unshared lone pair of electrons. FTP identify these compounds whose namesake is a doubly unsaturated, five-membered heterocyclic ether, which when fully saturated becomes the tetra-hydro version commonly used as an aprotic solvent.
Trionfo di_ Giulio _Cesare_  One method to synthesize substituted versions of these compounds begins with a Knoevenagel condensation between a beta dicarbonyl group and an alpha halogen ketone, and is known as the Feist-Benary synthesis.
{furan}s [generously prompt on "ether" until "thiophene"]