第一部份、設計合成以結合香豆素及?酮結構之化合物及其潛在熱致變色性質探討利用4-羥基香豆素(4-hydroxycoumarin)和?絳酚(anthrarufin) 經由5個反應步驟，總產率為3.38%，成功的合成出包含香豆素及?酮(anthrone)的化合物1，並探討其熱致變色性質。結果顯示，化合物1對熱並不敏感，即使在高溫80 ℃，或是低溫 -78 ℃下，都不具顏色的變化，並沒有如聯?酮(bianthrone)衍生物一樣，具有反摺疊型(anti-folded form)的立體構型上結構變化，推測其原因可能是香豆素上酮基的立體障礙與?絳酚之間的立體障礙不夠大所致。第二部份、設計合成以5-氮-4-羥基香豆素為主體的兩性離子化合物當作有機光氧化還原敏化劑我們分別設計合成出包含氯和硝基之5-氮-4-羥基香豆素為主體的兩性離子化合物，此類型的化合物具有當有機光氧化還原敏化劑的潛能。經由2-甲基-2-(4-硝苯基) -2,3-二氫-1H-呸啶進行光催化氧化反應做測試，發現這類型的化合物有催化氧化的能力。我們推測5-氮-4-羥基香豆素為主體的兩性離子化合物在可見光照射後，可經由還原淬滅循環(reductive quenching cycle)的途徑，催化2-甲基-2-(4-硝苯基) -2,3-二氫-1H-呸啶之氧化反應，並且推測可能的反應機構。 Part I: Design and synthesis of a coumarin/ anthrone-fused compound and its potential thermochromism studyA coumarin/anthrarufin-fused compound 1 was designed and synthesized in 5 steps with an overall yield of 3.38% to investigate its potential thermochromic properties. Unfortunately, the prepared compound 1, unlike bianthrone type thermochromic colorants, was found to be heat insensitive, and did not change color when being heated or at low temperature. The lack of the thermochromism of the prepared compound presumably due to the relative small steric hindrance between the coumarin and anthrarufin moieties.Part II: Design and synthesis of 5-aza-4-hydroxycoumarin-derived zwitterions as potential organophotoredox sensitizers Two chloro- and nitro-containing 5-aza-4-hydroxycoumarin-derived zwitterions were rationally designed and chemically synthesized in 6 steps to investigate their potentials to function as organophotoredox sensitizers. The oxidation of 2-methyl-2-p-introphenyl-2,3-dihydro-1H-perimidine was chosen as a model reaction to evaluate their catalytic ability. The results indicate that the designed zwitterions indeed can catalyze the oxidation upon visible light irradiation in ethanol via a reductive quenching cycle. A possible mechanism for this organic sensitizer-catalyzed perimidine oxidation is proposed.
