Synthesis and substitution reactions of β-alkoxyvinyl bromodifluoromethyl ketones

β-Alkoxyvinyl bromodifluoromethyl ketones 1a, 1b and 1c were synthesized by the reaction of bromodifluoroacetic anhydride with appropriate vinyl ethers in high yields. The acyclic enone 1a reacted with amines to give the corresponding β-aminovinyl bromodifluoromethyl ketones 2 in good yields. The reaction of 1a with electrophilic reagent ICl yielded α-iodoenone 4. The substitution reaction of the cyclic enones 1b and 1c with thio-nucleophiles gave the corresponding difluoromethylene thioethers 6. The three-component reactions of 2 with primary amines and formaldehyde gave multifunctional 1,2,3,4-tetrahydropyrimidine 3 in moderate yields.

Graphical abstractβ-Alkoxyvinyl bromodifluoromethyl ketones were synthesized by the reaction of bromodifluoroacetic anhydride with appropriate vinyl ether. Some electrophilic and nucleophilic reactions of the enones were studied, especially the SRN1 reactions of the enones with thio-nucleophiles. Figure optionsDownload full-size imageDownload as PowerPoint slide