Synthesis of 4,5-dihydrofuran derivatives. Stereochemical study of the reactions of 1,3-alkadienes with β-dicarbonyl compounds

4,5-Dihydrofuran derivatives were obtained by the reaction of cis- and trans-1,3-alkadienes with carbonyl compounds in the presence of the manganese (III) acetate/copper (II) acetate oxidizing system. It was observed that in the case of cis-1,3-alkadienes, in contrast to trans-1,3-alkadienes, inversion of the cis double bond, the degree of which depends on the structures of the unsaturated and carbonyl components of the reaction, occurs. It was shown that the reaction of cis-1,3-dodecadiene with diethyl malonate leads to the corresponding 1,4-addition product.Communic,ation 119 from the series Reactions of unsaturated compounds. See 1] for Communication 118.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 308–314, March, 1985.