壹、 新穎格里鈉試劑對二苯基硝基乙烯及其衍生物的1,8-加成反應 貳、 一鍋化合成雙環硝基苯併二氫吡喃及其衍生物

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2016

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摘要 本論文包含兩個主題,每個主是題各自獨立,內容含前言、研究動機、實驗結果與討論及結論。 第一個主題主要研究與探討格里納試劑與β-硝基苯衍生物的反應機構,格里納反應的反應機構是經由極性加成 (polar addition) 或是單電子轉移(Single Electron Transfer SET),一直以來常有爭論,經研究顯示:反應試劑立障大,如t-BuMgCl、溶劑極性強,如THF,則易以單電子轉移 (Single Electron Transfer SET),反之則易以極性加成 (polar addition) 路徑進行反應,本實驗使用1,1,2-三苯基-2-硝基乙烯或β-硝基苯衍生物與各種不同格里納試劑反應,以探討結果,在固定的溫度 (-25℃) 及THF為溶劑條件下,得到以極性加成路徑進行反應的1,4-加成產物,及以單電子轉移路徑進行反應得到 1,8-加成的產物;1,8-加成是一新穎的反應結果,目前並未有任何研究報告是有關格里納反應以1,8-加成的結果出現。 第二個主題主要是研究利用一鍋化簡單的合成出色 (Chroman),本實驗採用水楊醛 (Salicylicaldehyde) 4當量,環已胺 (Cyclohexyl amine) 5當量、硝基甲烷 (Nitromethane) 1毫莫耳 ‘ 醋酸 2毫升,在溫度80-90℃條件下約24小時即完成一鍋化反應,而得到高產率的單一結構三硝基色 (3-Nitro-chroman) 產物,本實驗提供了一個新穎的合成色 (Chroman) 的方法。 關鍵字: 極性加成、單電子轉移、1,1,2-三苯基-2-硝基乙烯、色
Abstract This thesis consists of two independent parts. Independently, each part has its own preface, motivation, discussion, experimental results, and conclusions. Research and discussion for the mechanism of the reaction between the Grignard reagent and β-nitrostyrene derivatives are discussed in the first section. Polar addition or single electron transfer has been a controversial issue in the Grignard reaction pathway. The previous studies showed the Grignard reagent with greater steric-hindered functionality, such as t-BuMgCl in polar solvent including THF, favors the SET reaction route; while the Grignard reactions with less steric crowding in non-polar solvents, such as ether were found to be via the polar addition route. The results of reactions of 1,1,2-triphenyl-2-nitroethane or β-nitrostyrene derivatives with several different kinds of Grignard reagents were discussed in this research work. Under -25℃inTHF, two different products were found to be 1,4-addition product via polar addition route and 1,8-addition product via single transfer electron route. 1,8-Addition product resulting from the Grignard reaction is novel since hitherto was not described. One-pot preparation of Chroman is the subject of the second part of this thesis. This one-pot synthesis was carried out under the following reaction condition to produce 3-nitro-chroman as an exclusive product with excellent yield. As such, salicylicaldehyde and cyclohexylamine along with nitromethane in (4:5:1) mixed in glacial acetic acid (2.0 ml) at 80-90℃for 24 hours. Therefore, a novel method for the preparation of Chroman was invented. Key word: polar addition、Single Electron Transfer、1,1,2-Triphenyl-2-nitroethene、Chroman

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極性加成, 單電子轉移, 1, 1, 2-三苯基-2-硝基乙烯, , polar addition, Single Electron Transfer, 1, 1, 2-Triphenyl-2-nitroethene, Chroman

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