以二芐環庚烷為衍生物的螺旋烯類化合物，此化合物可區分為上、下盤結構，依據其在結構上因立體效應與共軛效應的不同，分別合成一系列的螺旋烯類化合物。由x-ray 結構解析得知C(10)、C(11)上的乙基是位於equatorial的位置，可知環硫化合物是具有S掌性中心，所以環硫化合物在經由銅粉加熱進行去硫反應時，同相消去，得到的P的螺旋性化合物。此類化合物在基態吸收能量後躍遷至激發態時，連接上、下盤的雙鍵會形成雙自由基狀態，由激發態回到基態釋放能量的方式有二種： 一、形成雙自由基時，原本的雙鍵性質已改變為單鍵，可經由單鍵的旋轉而得到異構化的產物。本篇論文中以上盤為(10R, 11R, P)乙基取代、下盤為α-tetralone的螺旋烯類化合物，經由照射波長為280nm時，可得到幾乎是單一M形式的非鏡像立體異構物(M/P = 99.6/0.4)，再照射波長254nm(M/P = 33/67)則以P形式居多或者可經由加熱至130oC(M/P = 0/100)。所以整個受光所引導而產生的非鏡像超越(de)值為133%(由99.2%至-34%)，此一例子為目前可經由光異構化所得到最好的結果，將此結果引入K-15液晶材料中，得到P form的βM = 1.2μm-1(p = 133μm)，M form (99.2%de)的βM = 3.2μm-1(p = 50μm)。二、由於轉動能障較大，分子經由分子間的振動而將能量釋放出來。由實驗室發展各種不同類型的螺旋烯化合物，研究其光物理行為時發現，當改變不同的上、下盤結構時，造成顯著的差異而區分為三大系統：一、上盤以二芐環庚烷酮為基本骨架，下盤則依環張力、分子大小及共軛性來作為探討。二、上盤結構 C(10)，C(11)位置上加入乙基取代，增強其放光的效果，以及觀察Stokes Shift 的效應。第三系統是上盤為乙基取代，而下盤為β-naphtho-flavone 的螺旋烯類化合物，我們利用結構上的差異，使得吸收光譜到達可見光範圍(λmax = 367nm in n-hexane)，而其放射波長更可到達接近綠光範圍(λmax = 479nm in n-hexane) 。
關於此類分子，我們可應用於有機電致發光二極體元件(OLED)的dopant emitter，另外更合成下盤結構為雙嘧啶，以預期得到更好結果。

Three C2-symmetric (10R,11R)-diethyl substituted dibenzosuberane (DBS)-based helicenes with varying steric and conjugation demands of their bottom fragments were synthesized. The X-ray analyses of their precursors-episulfides reveal the preferred conformation of the DBS skeleton possessing equatorially oriented ethyl groups at C-8 and C-9 positions. In all cases, the absolute configuration in the episulfide moiety is S, which can lead stereospecifically to the corresponding P helicenes after the reductive desulfurization of the episulfides. Only the helicene-7a with the bottom part derived from -tetralone was found photoswitchable in reasonable time scale. Photoisomerization of the diastereomerically pure (10R,11R,P)-helicene (7a) at 280 nm led to virtually exclusive formation of the opposite M form-diastereomer 7a' (7a'/7a = 99.6/0.4). The preferential return of 7a' to 7a can be effected upon irradiation at 254 nm (7a'/7a = 33/67) or thermally at 130 C (7a'/7a = 0/100). The photoinduced switching process amounts to a 133% difference in de (from 99.2% to -34%). The concomitant change of helicene chirality between these two diastereomeric photostationary states augurs well for their potential application as an optical switch in LC materials. To our knowledge, our system serves as the best chirochromic optical switch as compared to the examples possessing similar photochromic properties

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