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研究生:王為錩
論文名稱:8,8-Dicyano,8,8-bis(Methoxycarbonyl)-heptafulvenes和6-Isopropyl,6-t-Butyl-6-phenylfulvenes之分子間[m+n]環化加成反應與反應機構研究
論文名稱(外文):Mechanistic Studies and Intermolecular [m+n] Cycloaddition Reactions of 8, 8-Dicyano, 8, 8-bis(Methoxycarbonyl)-heptafulvenes and 6-Isopropyl, 6-t-Butyl-6-phenylfulvenes
指導教授:劉清揚劉清揚引用關係
學位類別:碩士
校院名稱:文化大學
系所名稱:應用化學研究所
學門:自然科學學門
學類:化學學類
論文種類:學術論文
論文出版年:1994
畢業學年度:82
語文別:中文
論文頁數:94
中文關鍵詞:強缺電子基對稱雙取代弱缺電子基對稱雙取代
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強缺電子基對稱雙取代之8,8-dicyanohepta-fulvene(la)和給電子基不對稱雙取代之6-iso-propyl-6-Phenylfulvene(2e)在室溫下進行反應,可得到 [8+2]環化加成生成物17 (anti, endo)和 [4+2]環化加成生成物19a, b(Syn,endo);20a,b (anti, endo); 21 (syn, exo); 22 (anti, exo),以生成物17 為主要產物。如提高溫度以xylene迴流後,可得 [8+2]環化加成生成物18(anti, endo)及 [4+2]環化加成生成物19a,b;20a,b; 21; 22,以生成物19a為主要產物。環化加成生成物18 為生成物17經由 [1,5]-H轉移,而形成熱穩定之環化加成生成物。
強缺電子基對稱雙取代之1a和給電子基不對稱取代之6-t-butyl-6-phenylfulvene(2f)在室溫下進行反應,可得到 [4+2]環化加成生成物19c(syn, endo)及20c,d (anti, endo)。如提高溫度以Xylene。迴流後,得到與室溫相同的 [4+2]環化加成生成物,都以生成物20c為主要產物。
弱缺電子基對稱雙取代之8,8-bis(methoxy-carbonyl)heptafulvene。(1b)和給電子基不對稱雙取代之2e在室溫下進行反應,可得到 [8+2]環化加成生成物23 (anti, endo),如提高溫度以Xylene。迴流後,可得到 [8+2]環化加成生成物24 (anti, endo)及一些無法分離的產物,環化加成生成物24 為生成物23 經由 [1,5]-H 轉移,而形成對熱穩定之環化加成生成物。
弱缺電子基對稱雙取代之1b 和給電子基不對稱雙取代之2f 在較高溫度 8O℃進行反應,可得[4+2]環化加成生成物25。再提高溫度以 xylene迴流反應後,得相同生成物25。
當1a 和2e 在高溫進行環化加成反應時,有 [8+2],[4+2]環化加成生成物,以 Syn[4+2]為主要產物。而當1a 和2f 反應時,只有 [4+2]環化加成生成物,以anti [4。2]為主要產物.可能因2f 中之t-butyl官能基太大,而造成立體排斥力太大,使得 [8+2]環化加成生成物不易生成或形成後不穩定,而以立體排斥力小的anti [4+2]進行環化加成反應。


The cycloaddition reactions of electron-deficient symmetrical 8,8-dicyanoheptafulvene (1a) with electron rich unsymmetrical 6-iso-propyl-6-phenylfulvene (2e) at room tempera-ture give [8+2] adduct 17 (anti, endo), [4+2] adducts 19a,b (syn, endo); 20a,b (anti, endo); 21 (syn, exo); 22 (anti, exo), the adduct 17 is a chief product. When the reaction was carried out in refluxing xylene, [8+2] adduct 18 and [4+2] adducts 19a,b; 20a,b; 21; 22 were obtained. The adduct 19a is a chief product. Adduct 17 undervent a 1,5-sigmatropic hydro-genshift to yield the thermodynamically more stable adduct 18.
The cycloaddition reactions of electron-deficient symmetrical (1a) with electron rich unsymmetrical 6-t-butyl-6-phenylfulvene (2f) at room temperature give [4+2] adducts 19c (syn, endo) and 20c,d (anti, endo). When the reaction was carried out in refluxing xylene, [4+2] adducts 19c, 20c,d were formed. Adduct 20c is a chief product in the reactions.
The cycloaddition reaction of weaker electron-deficient symmetrical 8,8-bis (methoxy-carbonyl)heptafulvene (1b) with electron rich unsymmetrical (2e) at room temperature, yield only [8+2] adduct 23 (anti, endo). When the reaction was carried out in refluxing xylene, [8+2] adduct 24 (anti, endo) and undentified adducts were formed. The adduct 23 underwent a 1,5-sigmatropic hydrogenshift to yield the thermodynamically more stable adduct 24.
The reaction of weaker electron-deficient symmetrical (lb) with electron rich unsymmetrical (2f) in refluxing bezene, yielded only adduct 25 (anti, endo). When the reaction was carried out in refluxing xylene, only adduct 25 were formed.
The cycloaddition reaction of the (ia) with the (2e) at high temperature give [8+2], [4+2] adducts, the [4+2] syn regioisomers is the main products. When the (la) was reacted with the (2f), only the [4+2] adducts was obtained. The [4+2] anti regioisomers is the main product. The steric repulsion of the tbutyl substituent on the reaction of the (la) and the (2f) cause an is increased fomation of [4+2] adducts. In the cause of [4+2] cyclo-addition reaction, the [4+2] anti regioisomers is the main products.

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