A Convenient Synthesis of 2-Arylthiochromen-4-ones (Thioflavones) by Iodine-Mediated Cyclization of 3-Aryl-1-[2-(1,1-dimethylethylsulfanyl)phenyl]prop-2-en-1-ones
摘要:
A convenient two-step synthesis of 2-arylthiochromen-4-ones (thioflavones) beginning with 1-[2-(1,1-dimethylethylsulfanyl)phenyl]ethanones is described. Thus, 3-aryl-1-[2-(1,1-dimethylethylsulfanyl)phenyl]prop-2-en-1-ones were prepared by the condensation of 1-[2-(1,1-dimethylethylsulfanyl)phenyl]ethanones with aromatic aldehyde in the presence of sodium hydroxide, and were treated with iodine in refluxing N-methylpyrrolidin-2-one (NMP) or propanenitrile to afford the desired products in moderate to fair yields.
Iodine-Catalyzed Intramolecular Oxidative Thiolation of Vinylic Carbon-Hydrogen Bonds<i>via</i>Tandem Iodocyclization and Dehydroiodination: Construction of 2-Methylene-3-thiophenones
作者:Gang Zheng、Xiaoli Ma、Bangyu Liu、Ying Dong、Mang Wang
DOI:10.1002/adsc.201300815
日期:2014.3.10
A metal‐free vinylic carbon‐hydrogen bond thiolation has been developed. Under the catalysis of iodine (10 mol%), the cyclization of α‐alkenoyl ketene dithioacetals afforded a broad range of polyfunctionalized 2‐methylene‐3‐thiophenones in good selectivity with moderate to excellent yields via tandem iodocyclization and dehydroiodination. The synthetic strategy can also be extended to the cyclization