Iodine-catalyzed synthesis of β-keto enol ethers

Toxicity and Synergism in the Feeding Deterrence of Some Coumarins onSpodoptera frugiperdaSmith (Lepidoptera: Noctuidae)

“…See [18] [19]. As displayed in the Scheme, the dione D could be converted into the compound 7 through a surfacemediated Michael addition with methyl vinyl ketone (MVK), supported on activated neutral Al 2 O 3 , without any solvent, and further treatment with I 2 and MeOH according to the following procedure.…”

Molecular iodine-catalyzed one-pot synthesis of some new Hantzsch 1,4-dihydropyridines at ambient temperature

“…Molecular iodine [28][29][30][31] has attracted attention as an inexpensive, non toxic, readily available catalyst for various organic transformations to afford the corresponding products in excellent yields with high selectivity. It has been used as a mild Lewis acid in the dehydration of tertiary alcohols to alkenes, in the formation of ethers, as well as β-keto enol ethers, [32][33][34] for esterification, 35 transesterification, 36 acetylation 29 and benzothiophene 37 formation, but there are only a few reports about its use for the synthesis of 1,4-DHPs. 38,39 Therefore, we decided to synthesize some new symmetrical, unsymmetrical and N-substituted 1,4-DHPs promoted by a catalytic amount of iodine under ambient conditions with good to excellent yields.…”

Iodine-Catalyzed One-Pot Synthesis of 2H-Pyrans by Domino Knoevenagel/6π-Electrocylization

“…Iodine-catalyzed and -mediated syntheses of benzyl alkyl ethers, 19 benzothiophenes, 20 bis-indols, 21 β-keto enol ethers, 22 chalcones, 23 quinolines, 24 and isoquinolines 25 were already reported. However, iodine-catalyzed formal [3+3] cycloadditon of 1,3-carbonyls to α,β-unsaturated aldehydes to afford 2H-pyrans has not been examined.…”