臺灣博碩士論文加值系統

本論文主要探討具光學活性胺配位基與金屬四重鍵化合物的化學。 藉由起始物[Mo2Cl4(PPh3)2(CH3OH)2]分別與含旋光性之單芽胺配位基(L)(L = S-chea, R-chea, S-nea,R-nea, S-mba, R-mba, S-dmba, R-dmba)在丙酮中反應,可得到產物[Mo2Cl4(S-chea)4],1,[Mo2Cl4(R-chea)4], 2,[Mo2Cl4(S-nea)4], 3,[Mo2Cl4(R-nea)4], 4,[Mo2Cl4(S-mba)4],5,[Mo2Cl4(R-mba)4],6,[Mo2Cl4(S-dmba)4],7,[Mo2Cl4(R-dmba)4],8。它們的UV-vis和CD光譜已有記錄,同時化合物1和2的結構也已被決定。從結構中可知，Mo原子在兩者晶體結構中被發現具有diorder的特性。化合物1和2，主要與次要結構的比例分別為97:3和94:6。由CD光譜顯示出[Mo2Cl4(L)4]型式化合物在固體態時與在溶液中，構形是相反的。化合物在溶劑中的變溫CD光譜皆交叉於isosbestic point，這表示每一個化合物的一對構形之間隨著溫度變化在此達到平衡。Wood-Fickett-Kirkwood的方法已經 被用於去計算Delta和Lambda構形間的自由能變化，並且可得到它們在溶液中所佔的比例。Mo2Cl4(etp)(THF)]與具有旋光性的單芽胺配位基(L)反應時，可得到[Mo2Cl4(etp)(L)]型式的化合物。其光譜顯示出，當化合物中胺配位基的旋光性為R 時，其在最低能帶躍遷之相位為正，在第二最低能帶躍遷之相位為負﹔而旋光性為S 時，其在最低能帶躍遷之相位 為正，在第二最低能帶躍遷之相位為正。單芽胺配位基(L)[(S-chea) = S-(+)-1-cyclohexylethylamine,(R-chea) = R-(-)-1-cyclohexylethylamine,(S-nea) = S-(-)-1-(1-naphthyl)ethyl-amine,(R-nea) = R-(+)-1-(1-naphthyl)ethylamine,(S-mba) = S-(-)-α-methylbenzyl-amine,(R-mba) = R-(+)-α-methylbenzylamine,(S-dmba) = S-(-)-α,4-dimethyl-benzylamine,(R-dmba) = R-(+)-α,4-dimethylbenzylamine]。化合物1 的晶體資料:空間群為I222,a = 6.899(1) 埃，b = 15.594(3)埃，c = 19.296(4)埃，V = 2076(1)埃三次方，Z = 2，R = 0.0576，Rw = 0.0585。化合物2 的晶體資料:空間群為I222，a = 6.900(1)埃，b = 15.588(3)埃，c = 19.278(4)埃，V = 2073(1)埃三次方，Z = 2，R = 0.0577，Rw = 0.0611。

This thesis discusses the chemisty of quadruply bonded complexes containingchiral amine ligands.The complexes of [Mo2Cl4(S-chea)4], 1,[Mo2Cl4(R-chea)4], 2,[Mo2Cl4(S-nea)4], 3,[Mo2Cl4(R-nea)4], 4,[Mo2Cl4(S-mba)4], 5,[Mo2Cl4(R-mba)4], 6,[Mo2Cl4(S-dmba)4],7, and [Mo2Cl4(R-dmba)4],8 were prepared by reactions of[Mo2Cl4(PPh3)2(CH3OH)2] with monodentate chiral amine ligands S-chea,R-chea,S-nea,R-nea,S-mba,R-mba,S-dmba and R-dmba in acetone, respectively. Their UV-visand circular dichroism spectra have been recorded and the structures of 1 and2 have been determined.The molybdenum atoms in both crystal structures werefound to be disordered.The ratios of the primary to the secondary form are 97:3and 94:6 for 1 and 2,respectively.The CD spectra show opposite conformers forthe complexes in the solid-state and in solution.The variable-temperature CD spectra of the complexes in solvent intersect in isosbestic points,indicatingtemperature-dependent equilibria between pairs of conformers for each complex.The Wood-Fickett-Kirkwood method has been used to calculate the free-energy changes of the Delta and Lambda conformers and their populations in solution.The reactions of [Mo2Cl4(etp)(THF)] with monodentate chiral amine ligands(L) produce complexes of the type [Mo2Cl4(etp)(L)].The complex with ligands with ligands in R configurations shows a positive phase for the lowest energy bandtransition and a negative phase for the second lowest energy band transition inthe CD spectra, while that with ligands in S configurations shows a negativephase for the lowest energy band transition a positive phase for the second lowest energy band transition.