• Bulletin of the Korean Chemical Society
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• 제28권9호
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• pp.1553-1561
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• 2007

The new type of heterometallic chiral polymer salen complexes have been synthesized and it has been found that group 13 metal salts (AlCl3, GaCl3 and InCl3) combined to cobalt salen unit played the crucial role in the asymmetric kinetic resolution of racemic epoxides. Polymeric salen catalysts showed very high reactivity and enantioselectivity for the asymmetric ring opening of terminal epoxide with diverse nucleophiles. They provide the enantiopure useful chiral intermediates such as chiral terminal epoxides and α -aryloxy alcohols in one-step process. An efficient methodology for providing very high enantioselectivity can be achieved in the synthesis of valuable chiral building blocks via our catalytic system by combination of various asymmetric ring opening reactions.

• 대한화학회지
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• 제46권3호
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• pp.194-204
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• 2002

Cl- 이온을 포함하는 일련의 salen형 착물 {[Mn(III)($L_{acn}$)CI]: n=1~11} 들은 $Mn(CH_3COO)_2{\cdot}4H_2O$와 네자리 칸막이 리간드 {$H_2L_{acn}$}로 부터 얻었다. 이 salen형 리간드는 diamine류 {ethylenediamine, 1,3-propnediamine, 2,2-dimethyl-1,3-propanediamine, o-phenylenediamine}와 aldehyde류 {salicylaldehyde, 5-chlorosalicyladehyde, 3,5-dichlorosalicyladehyde, 3,5-di-tert-butyl-2-hydroxybenzaldehyde}를 lmethanol 용액에서 축합반응시켜 합성하였다. 이들 리간드 및 착물들은 원소 분석, 전도도, 열분석법 및 UV-VIS IR, NMR 분광학법 등을 이용하여 확인 고찰하였다.

• Bulletin of the Korean Chemical Society
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• 제31권4호
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• pp.829-834
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• 2010

Ligand variation was carried out on a cobalt(III) complex of Salen-type ligand comprised of 1,2-cyclohexenediamine and salicylaldehyde bearing a methyl substituent on 3-position and -[$CMe(CH_2CH_2CH_2N^+Bu_3)_2$] on 5-position, which is a highly active catalyst for $CO_2$/propylene oxide copolymerization. Replacement of the methyl substituent with bulky isopropyl group resulted in alteration of the binding mode, consequently lowering turnover frequency significantly. Replacement with an ethyl group preserved binding mode and activity. Replacement of the tributylammonium unit with trihexylammonium or trioctylammonium, or replacement of 1,2-cyclohexenediamino unit with -$NC(Me)_2CH_2N$- decreased activity, even though the binding mode was unaltered.

• Bulletin of the Korean Chemical Society
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• 제30권2호
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• pp.389-396
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• 2009

MFI structural zeolite (ZSM-5 or Sililcalite) was treated with HF solution to introduce mesoporous channels in the microporous crystals. Inner mesopore size could be controlled from 2.5 to 3.5 nm by changing the concentration of HF solution. The pore structure of HF-treated MFI zeolite was studied by instrumental analysis. The active Co (III) salen complex monomers were successfully anchored non-covalently on the surfaces of mesoporous MFI-type zeolite. These heterogeneous catalysts could be applied in asymmetric ring opening of terminal epoxides by phenol derivatives. It showed very high enantioselectivity and yield up to 95% in the catalytic synthesis of optically active $\alpha$-aryloxy alcohol compounds.

• 공업화학
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• 제20권3호
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• pp.279-284
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• 2009

모더나이트결정 중의 실리카를 제어된 알칼리용액의 처리로 추출제거하여 중간세공이 형성되도록 하였다. 형성된 중간세공의 크기는 알칼리용액의 농도를 변화시킴으로써 조절할 수 있었다. 알칼리처리 후의 모더나이트 제올라이트 내부의 세공구조를 조사하였다. 새둥지형태의 중간세공을 형성시키기 위해서는, 알칼리용액 처리전에 모더나이트결정의 바깥표면을 티타니아로 코팅하는 것이 가장 효과적임을 관찰하였다. 모더나이트 내부의 중간세공에 고분자형의 코발트(III) 살렌착체를 "ship-in-a-bottle"법으로 가둔 촉매를 제조하였다. 이 고정화촉매를 물에 의한 에피클로로히드린의 산소고리열림반응에 사용하여, 촉매반응에서 높은 수율과 광학선택성을 얻을 수 있었다.