Application Research Of 2-Hydroxyalkyl Phenyl Selenide Reagents In Organic Synthesis

In this dissertation, applications of 2-hydroxyalkyl phenyl selenide reagents in organic synthesis were investigated.Firstly, Vinyl ethers were prepared in a one-pot, two-step transformation by O-alkylation reaction of 2-hydroxyalkyl phenyl selenides with primary or secondary organic halides followed by oxidation-elimination with 30 % hydrogen peroxide. The present method has advantages such as mild reaction condition, easy manipulation and moderate to good yield (70-85%).Secondly, A novel three-step, one-pot synthesis of 2-oxazolidinones from phenyl 2-hydroxyalkyl selenides was developed. Using this methodology, 2-oxazolidinones are produced in good yields (76-85%) by a reaction of phenyl 2-hydroxyalkyl selenides with benzoyl isocyanate and subsequent oxidation/cyclization, followed by hydrolysis with hydrochloric acid solution. The procedure provided a convenient and wild method for the preparation of 2-oxazolidinone derivatives.Finally, Treatment of 2-hydroxyalkyl phenyl selenides with acryloyl chloride or propiolyl chloride in the presence of Et₃N afforded the corresponding acrylates or propiolates, which were further treated with InCl₃/NaBH₄ by radical deselenation-cyclization reaction to produce the corresponding γ-butyrolactones and exo-methylene γ-lactones in moderate to good yields (75-85 %). This procedure furnished a new methodology for preparation of substituted (3,5-di and 3, 4, 5-tri) γ -lactones and substituted (5- and 4, 5-di) 3-methylene-γ-lactones.