6948-60-3Relevant articles and documents
Conjugate addition of grignard reagents to thiochromones catalyzed by copper salts: A unified approach to both 2-alkylthiochroman-4-one and thioflavanone
Austin, Nataleigh,Bellinger, Tania J.,Deese, Nichele,Guo, Fenghai,Harvin, Teavian,Hukins, Dabria T.,Pickens-Flynn, Ti'Bran,Tutein, Mai Ling C. Tang Yuk,Whitaker, Samuel H.
, (2020/05/25)
Grignard reagents undergo conjugate addition to thiochromones catalyzed by copper salts to afford 2-substituted-thiochroman-4-ones, both 2-alkylthiochroman-4-ones and thioflavanones (2-arylthiochroman-4-ones), in good yields with trimethylsilyl chloride (TMSCl) as an additive. The best yields of 1,4-adducts can be attained with CuCN-2LiCl as the copper source. Excellent yields of 2-alkyl-substituted thiochroman-4-ones and thioflavanones (2-aryl substituted) are attained with a broad range of Grignard reagents. This approach works well with both alkyl and aromatic Grignard reagents, thus providing a unified synthetic approach to privileged 2-substituted thiochroman-4-ones and a potential valuable precursor for further synthetic applications towards many pharmaceutically active molecules. The use of commercially available and/or readily prepared Grignard reagents will expedite the synthesis of a large library of both 2-alkyl substituted thiochroman-4-ones and thioflavanones for additional synthetic applications.
