Synthesis of novel fluorinated derivatives of 1,3-dimethylbarbituric acid

Article abstract of DOI:10.1016/S0040-4020(98)00329-9

Synthetic utility of the novel difluoro ketene aminal 1 was extended to the preparation of a number of potentially biologically-interesting difluoro barbituric acid derivatives via initial hetero-Diels-Alder reactions of 1 with p-substituted-5-benzylidene-1,3-dimethylbarbituric acids 3. These cycloadducts 4 upon hydrolysis, provided the formal Michael addition product amides 5 which were readily converted to the respective carboxylic acids 6. The acids were dehydratively cyclized to form novel bicyclic lactones 8.