• 제목/요약/키워드: Structural Characterization

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N,N'-Bis[2(S)-2-pyrrolidinylmethyl]phenylene-1,2-diamine를 배위하는 전이금속 착물의 합성 및 구조적 특성 (Synthesis and Structural Characterization of Transition Metal Complex with N,N'-bis-[2(S) -pyrrolidinylmethyl]phenylene-1,2-diamine)

  • 김동엽
    • 한국산업융합학회 논문집
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    • 제1권1호
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    • pp.43-49
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    • 1998

  • The SS-phpm 4HCl(N,N'-bis-[2(S)-pyrrolidinylmethyl]phenylene-l,2-diamine-4-Hydrochloride) ligand having stereospecificity has been prepared and reacted with trans-[$Co(pyridine)_4Cl_2]$Cl. The resultants are purple crystals, which are identified to be ${\Delta}$-cis-${\beta}$-[$Co(SS-phpm)Cl_2$]Cl by elemental analysis and UV/Vis- and CD-absorption spectra, The conformation of SS-phpm in ${\Delta}$-cis-${\beta}$ complex is ${\delta}$ ${\varepsilon}$ ${\lambda}$ (SSSS) for each of the five-membered chelated ring. Futhermore, according to orientation of secondary amine, total strain energy on each isomers was calculated by molecular mechanics(MM) to verify structural characterization and spectral data. As the result, the most stabilized isomer was ${\Delta}$-cis-${\beta}$(SSSS). The value of total strain energy(U) of ${\Delta}$-cis-${\beta}$(SSSS) isomer was 63.21 kcal/mol, respectively.

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Synthesis and Characterization of Cationic and Anionic Cyclodextrin Oligomers and Their Use in Layer-by-Layer Film Formation

  • Yang, Sung Yun;Hoonor, Rekha;Jin, Hye-Seung;Kim, Jeongkwon
    • Bulletin of the Korean Chemical Society
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    • 제34권7호
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    • pp.2016-2022
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    • 2013

  • Ionically modified ${\beta}$-cyclodextrins, which have excellent water-solubility, have been interested in purification technology as well as drug carrier system. The present study summarizes the synthesis and characterization of cationic and anionic ${\beta}$-cyclodextrin (${\beta}$-CyD) products using by polycondensation. The oligo (${\beta}$-CyD)s are synthesized from ${\beta}$-CyD, epichlorohydrin (EP) and choline chloride (CC; for cationic polymer) or chloroacetic acid (CAA; for anionic polymer) through one step polycondenstaion process. Unlike the previous studies, we successfully purified the ionic ${\beta}$-CyD condensation products from the ${\beta}$-CyD reaction mixtures and accomplished a great level of structural analysis. The detailed structural analysis of these ionic ${\beta}$-CyD compounds is done by $^1H$ NMR, MALDI-TOF as well as GPC analysis and confirms the formation of oligomers with a few units of ${\beta}$-CyD. We found that the sequence of reactant addition also could effect on the molecular weight of the resulting product as well as the molar ratio of the reactants. Finally, we used the cationic and anionic ${\beta}$-CyD oligomers for fabricating multilayer films by layer-layer process.

  • https://doi.org/10.5012/bkcs.2013.34.7.2016 인용 PDF KSCI