雜環奎若林鄰昆二前驅物的合成及其在Diels-Alder反應上的應用

Abstract

雜環□□□鄰□二烯前驅物的合成 及其在 Diels-Alder 反應上的研究 研究生：黃敏惠 指導教授：鍾文聖 博士 國立交通大學應用化學研究所 摘 要 近年來，本實驗室致力於雜環□□□鄰□二烯前驅物的研究，我們已製備出多種quinoxalino-sultine作為□□□鄰□二烯的前驅物，利用sultine分子易於脫去SO2的性質，所製備的前驅物在高溫（150 ~ 200 oC）及照光（254 nm）下，可生成其□□□鄰□二烯，並與一些常見的親雙烯體進行Diels-Alder反應。在本論文中，我們合成出2,3-diphenylquinoxalino-6,7-sultine (55c) □□□鄰□二烯的前驅物，並對它們的熱化學與光化學反應進行研究。 這一系列的雜環 sultine 分子在 200 oC 封管反應時，均會脫去SO2分子生成其o-QDM中間體，與親雙烯體反應時均可以高產率地得到其Diels-Alder環化加成產物。而在光化學反應中 (以 254nm 波長照光)，我們除了獲得與熱化學相同的環合產物外，亦會得到其異構化產物sulfolene和一些不溶的高分子聚合物。 將 quinoxalino-fused sultine (47d)、(55b-c)、2,3-bis(bromomethyl)- 5,10-benzo[g]quinoxalinedione (94) 和 naphtho-sultine (113) 與 C60反應時，均可以很成功地到和 C60 的單一加成產物。經由變溫 1H-NMR 實驗研究發現，這些 C60 單一加成產物中氮原子存在與否以及和 C60間的距離對於其上六員環的構形交換速率有很大的影響。 在雷射瞬態光譜的研究中，我們以 248 nm 的雷射光光解 sultine，可以偵測到中間物的生成，極有可能是我們所欲偵測的 o-QDM 或 biradical 中間體，但仍須進一步的理論計算與實驗來驗證。

Abstract The goal of our research is to synthesize the precursors for quinoxalino-o-quinodimethanes, and to explore their potential application in Diels-Alder reaction. The advantage of using sultines is their ease of SO2 extrusion at lower temperature than the corresponding sulfolenes. After successfully synthesizing 2,3-diphenylquinoxalino-6,7-sultine (55c), we have studied their thermochemistry and photochemistry. These heterocyclic sultines extrude SO2 and form the corresponding o-quinodimethanes at high temperature (200 oC), which in turn react with dienophiles to give excellent yield of cycloadducts. The products from photochemical reactions (irradiated with 254 nm UV-light) are similar to those from thermochemical reactions besides that corresponding sulfolene and some quantity of insoluble ploymers are formed photochemically. When quinoxalino-fused sultine (47d)、(55b-c), 2,3-bis (bromomethyl) -5,10-benzo[g]quinoxalinedione (94) and naphtho-sultine (113) are heated with C60, the mono-Diels-Alder-adducts of the C60 are obtained successfully. Variable temperature 1H-NMR experiments show that the sxistence of nitrogen atoms and the distance between the nitrogen atoms and C60 core may have a great influence on the rate of boat-to-boat conformations exchange of C60 mono-adducts. Laser flash photolysis (248 nm) on these quinoxalino-sultine leads to the detection of a new transient spices, which is very likely to be the corresponding o-quinodimethane or biradical intermediates. Further work and theoretical calculation is needed to confirm these observations.