Development of CD Method and Applications to Stereochemistry

CD光谱法与x射线晶体学法是测定手性有机化合物绝对立体结构的有效方法。作为CD激子手性方法的扩展，我们提出了一种非经验测定扭曲pi电子体系绝对立体化学性质的新理论方法。CD谱可以用pi-电子SCF-CI-DV分子轨道法进行理论计算，并确定了以下生物活性天然产物和具有理论意义的合成手性有机化合物的绝对立体结构。澄清了适合CD激子手性法研究低聚糖的红甲氧基肉桂酸发色团的电子结构。用CD法和x射线法测定了12-羟基化新氯罗德烷二萜中C-12的绝对立体化学。合成了分子不对称的手性烯烃，并对其绝对立体结构进行了测定。阐明了它们的光外消旋和热外消旋的动力学和机理。研究了手性桥联苯的CD和绝对立体化学。我们发现一种手性双花青素染料在紫外-可见吸收光谱和CD光谱中表现出异常强烈的激子分裂，并阐明了其独特激子耦合行为的来源和性质。我们建立了一种CD激子法来测定无环1,3-二苯甲酸酯体系的绝对立体化学。澄清了其独特激子耦合行为的起源和性质。合成了包括[6,6]-螺芴在内的9,9′-螺芴骨架手性螺芳香化合物，并用CD法测定了它们的绝对立体结构。通过CD谱的理论计算，首次成功测定了阿托异构体双黄酮(-)-4′，4′，7′，7′-四- o -甲基柏素黄酮的绝对立体化学性质。研制了一种用于光学分辨和x射线晶体学测定手性羧酸绝对立体化学的手性探针。通过x射线晶体学和CD光谱研究，我们修正了(8)和(10)-副环烷羧酸的绝对立体化学，这是以前根据化学相关性错误地确定的。少

The CD spectroscopic method, together with the X-ray crystallographic method, is useful for determination of the absolute stereostructure of chiral organic compounds. We have proposed, as an extension of the CD exciton chirality method, a new theoretical method for nonempirical determination of the absolute stereochemistry of twisted pi-electron systems. The CD spectra can be theoretically calculated by the pi-electron SCF-CI-DV molecular orbital method, and we have determined the absolute stereostructures of the following biologically active natural products and synthetic chiral organic compounds with theoretical interest.1.The electronic structure of rho-methoxycinnamate chromophore suitable for application of the CD exciton chirality method to oligosaccharides was clarified.2.absolute stereochemistry at C-12 in 12-hydroxylated neo-clerodane diterpenoids was determined by CD and X-ray methods.3.Chiral olefins with molecular asymmetry were synthesized, and their absolute stereostructu … More res were determined by the CD method. the kinetics and mechanism of their photo and thermal racemization were also clarified.4.CD and absolute stereochemistry of chiral bridged biphenyls were studied.5.We found that a chiral biscyanine dye exhibits unusually strong exciton split in UV-VIS absorption and CD spectra, and the origin and nature of its unique exciton coupling behavior were clarified.6.We developed a CD exciton method for determination of the absolute stereochemistry of acyclic 1,3-dibenzoate systems.d the origin and nature of its unique exciton coupling behavior were clarified.7.Chiral spiroaromatic compounds with 9,9'-spirobifluorene skeleton including[6,6]-vespirene were synthesized and their absolute stereostructures were determined by the CD method.8.We have succeeded in the first determination of the absolute stereochemistry of atropisomeric biflavone, (-)-4',4''',7,7''-tetra-O-methylcupressuflavone, by theoretical calculation of CD spectra.9.A chiral probe useful for optical resolution and X-ray crystallographic determination of the absolute stereochemistry of chiral carboxylic acids was developed.10.We revised, by X-ray crystallographic and CD spectral studies, the absolute stereochemistry of (8)-and(10)-paracyclophane carboxylic acids previously erroneously determined on the basis of chemical correlation. Less