Applications Of Hydrogen Peroxide In Organic Synthesis

In this thesis, the following four parts are mainly included: Chapterâ… : Recent progress of hydrogen peroxide in organic synthesisIn this chapter, epoxidation of alkenes, selective oxidation of alcohols, oxidation of sulfides to sulfoxides and sulphones, halogenation of organic compounds carried out using hydrogen peroxide were summarized. The references all were published in leading international journals. Chapterâ…¡: Aromatization of Hantzsch 1,4-dihydropyridines by H₂O₂/V₂O₅A series of Hantzsch 1,4-dihydropyridines were synthesized in an environmentally benign method , by reacting aldehydes with acetoacetate esters and ammonium acetate at 80℃. We have chosed several catalysts and found that H₂O₂/V₂O₅ was a good system for the aromatization of Hantzsch 1,4-dihydropyridines to the correspondence pyridines. A possible reaction mechanism was also suggested. The cheapness, easy availability of the reagents, mild reaction conditions as well as excellent yields of the products are the advantages which make this protocol a useful addition to the existing methodologies. Chapterâ…¢: Aromatization of Hantzsch 1,4-dihydropyridines by H₂O₂/Ti(SO₄)₂Hantzsch 1,4-dihydropyridines undergo smooth aromatization catalyzed by a catalytic amount (5mol%) of Ti(SO₂)₂ with H₂O₂ to afford the corresponding pyridine derivatives in high yields. Various solvent systems were tested. All the reactions were carried out in acetonitrile at room temperature for eight hours to complete conversion of the substrates. The cheapness of the catalyst and the oxidizer were employed. Chapterâ…£: Selective oxidation of alcohols to aldehydes and ketones with H₂O₂/Ti(SO₂)₂In this chapter, the selective oxidation of alcohols to aldehydes and ketones with H₂O₂/Ti(SO₄)₂ have been accomplished. All of the substrates gave the excellent yields except the p-nitrobenzyl alcohol and the benzyl alcohol.The above results reference values in enlarging the application field of hydrogen peroxide in organic synthesis. We think that the use of V₂O₅ and Ti(SO₄)₂ catalysts with hydrogen peroxide in organic synthesis were worth to being referred.