Write short notes on Synthesis of benzofuran.
Answers
Benzofuran is the heterocyclic compound consisting of fused benzene and furan rings. This colourless liquid is a component of coal tar. Benzofuran is the "parent" of many related compounds with more complex structures. For example, psoralen is a benzofuran derivative that occurs in several plants.
Benzofurans can be prepared by various methods in the laboratory. Notable examples include:
O-alkylation of salicylaldehyde with chloroacetic acid followed by dehydration (cyclication) of the resulting ether and decarboxylation.[3]
Benzofuran.png
Perkin rearrangement, where a coumarin is reacted with a hydroxide:[4][5][6]
Perkin rearrangement
Diels–Alder reaction of nitro vinyl furans with various dienophiles:[7]
Diels–Alder reaction yielding a substituted benzofuran
Cycloisomerization of alkyne ortho-substituted phenols:[8]
Benzofurans via Cycloisomerization