A Convenient Synthesis of 3-Fluorinated 2-Oxopropyl Sulphoxides from Fluorinated Lithium Acetates and 1-Lithioalkyl Sulphoxides
作者:Pierfrancesco Bravo、Elena Piovosi、Giuseppe Resnati
DOI:10.1055/s-1986-31714
日期:——
Optically pure methyl 4-methylphenyl sulphoxide and ethyl 4-methylphenyl sulphoxide are metallated with lithium diisopropylamide and then subjected to the reaction with fluorinated lithium acetates or acetic esters. C-Acylation proceeds smoothly and regioselectively to give high yields of chiral 3-fluorinated 2-oxopropyl 4-methylphenyl sulphoxides. The analogous reaction of dimethyl sulphoxide with fluorinated lithium acetates affords good yields of racemic 3-fluorinated 2-oxopropyl methyl sulphoxides. As examples of further reactions of the products, C-methylation, S-deoxygenation, and carbonyl reduction of 3-fluoro-2-oxopropyl 4-methylphenyl sulphoxide are described.
光学纯的 4-甲基苯基亚砜甲基和 4-甲基苯基亚砜乙基与二异丙基酰胺锂发生金属化反应,然后与氟化乙酸锂或乙酸酯发生反应。C-酰化反应顺利进行,并具有区域选择性,从而得到高产率的手性 3-氟化 2-氧代丙基 4-甲基苯基亚砜。二甲基亚砜与氟化乙酸锂发生类似反应,可以得到外消旋 3-氟化 2-氧代丙基甲基亚砜。作为产品进一步反应的实例,介绍了 3-氟-2-氧代丙基 4-甲基苯基亚砜的 C-甲基化、S-脱氧和羰基还原反应。