Studies On The Application Of PEG400 As Phase Transfer Catalyst In The Solid-Liquid Phase Organic Synthesis

Studies on the application of phase transfer catalyst PEG400 in the anhydrous solid-liquid organic synthetic reactions were carried out. The thesis consists of five chapters.Chaper 1: The useful synthetic reagent trimethylsilyl cyanide was readily prepared in high yield by the cyanation of trimethylchlorosilane with potassium cyanide catalyzed by phase transfer catalyste PEG400 and zinc iodide under stirring at room temperature. 2 hours were need for the reaction to be completed when acetonitrile was used as solvent. The final product couldn't be separated from azeotropic mixture and GC showed a proportion of 92-94% of product was obtained. When dichloromethane was used as solvent the reaction time was elongated to 24 hours and a yield of 83% of the product with high purity was achieved. The reaction performed under ultrasonic irradiation could greatly shorten the reaction time to 6 hours.Chaper 2: Two classes of important reagents trialkyllsilyl pseudohalides and trimethylsilyl carboxylate were prepared by the reaction of trimethylsilyl chloride or triethyl chloride with sodium isocyanate, potassium thiocyanate, sodium cyanide, sodium azide, sodium acetate, propionate, and benzoate under the catalysis of PEG400 and zinc iodide in dichloromethane at room temperature. A study on the reaction of trimethylchlorosilane with inorganic oxysalts such as sodium nitrite, nitrate, carbonate, sulfite and potassium chlorate, with which chlorine dioxide was generated, was reported for the first time.Chaper 3: Nine aroyl cyanides were readily synthesized in moderate yields under mild conditions by the cyanation of aroyl chlorides with potassium cyanide under the catalysis of PEG400 and zinc iodide in dichloromethane at room temperature, with few dimers formed. A preliminary study on the one-pot preparation of acetyl cyanide was also reported. In addition, a low yield of a -[(trimethylsilyl)oxy] acrylonitrile was also obtained.Chaper 4: Thioacetates are conveniently prepared in high yields under mild condition by the reaction of alkyl halides and sodium thioacetate, prepared in situ from thioacetic acid and sodium carbonate, catalyzed by PEG400 at room temperature. The present method has the advantages of milder reaction, shorter reaction time, simplicity of work up, recoverability of solvents, and might be applicable into industrial production. Chaper 5: Starting from nitrobenzene, m-bromoanisole was synthesized in four stepsinvolving bromination, reduction, diazotization, hydrolysis and etherification. The etherification was catalyzed by PEG400 in the absence of solvent.