1.3- Dienes reaction with 5-ethoxy-2-pyrrolidinone

Intermolecular reactions of species (69) with simple alkenes have received little attention. Recently, a study of the reaction of 5-ethoxy-2-pyrrolidinone with several 1,3-dienes in the presence of acid was published. When a mixture of ethoxylactam and 2,3-dimethylbutadiene is stirred in neat formic acid, the formates (73) and (74) are isolated as the main products in 43% yield. The bicyclic product (75) is obtained in only 16% (equation 38). If the reaction is carried out in benzene with p-toluenesulfonic acid as catalyst (75) is formed in 19% yield. Other dienes show similar behavior, producing bicyclic compounds as byproducts in low to moderate yields except for one or two cases, as illustrated with com-... 

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See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

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