Studies On The Cyclization Reaction Of α-oxo Ketene Dithioacetal With Propargyl Alcohol

Functionalized α-oxo ketene dithioacetals are versatile intermediates in organicsynthesis and have very important use. One of the most important use is it can beassociated with a variety of having a nucleophilic reaction of the material. A varietyof heterocyclic compounds can be synthesized, such as five membered ring ofNitrogen, Sulfur and Oxygen heterocyclic compounds and fused ring compounds.Propargyl alcohol has a nucleophilic oxygen atoms; Whlie, C-C triple bond hashigh density of electronic cloud and a tube-shaped distribution is formed between theC-C. Carbon nuclear attract electron not firmly. Electron flow easily and unevenlydistribute between the C-C, which caused Π electron are easily polarized. This specialstructure determine that the C-C triple bond can take electrophilic reaction.Based on the features of the α-oxo ketene dithioacetals (the high electronic clouddensity of α-C can be used as a nucleophilic center, β-C as a electrophilic center) andthe characteristics of propargyl alcohol, α-oxo ketene dithioacetals as1,2dipole andpropargyl alcohol as1,3dipole react to generate a series of furan ketones underalkaline conditions after taking nucleophilic addition elimination reaction, desacetyl,(3,3’) migration and cyclization reaction. The advantages of the synthesis reactioninclude mild conditions and inexpensive reagents.