Reactions of aromatic and heteroaromatic compounds bearing electron-acceptor substituents

Complexing with aluminum chloride can change the specificity of the bromination of furfural in such a way that the major product becomes 4-bromofurfural. Consequently, as in the thiophene series, reinforcement of the electron-acceptor capacity of the carbonyl group by means of the complexing deactivates the free 5 position so much that the 4 position of the furan ring becomes the most active.See [1] for communication X.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 597–600, May, 1972.