• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.2965-2969
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• 2011

Highly efficient and rapid aminolysis of epoxides with various amines in water under microwave irradiation in the absence of catalyst was developed. Chiral ${\beta}$-amino alcohols were formed in a short time with excellent yields.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.198-198
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• 2011

Organocatalysis is a relatively new and popular area within the field of chiral molecule synthesis. It is one of the main branches of enantioselective synthesis with enzymatic and organometallic catalysis. In recent years, immense high quality studies on catalysis by chiral secondary amines were reported. These progresses instantly led to different organocatalytic activation concepts, so thousands of researchers from academia and the chemical industry are currently involved in this field and new ideas, new approaches, and creative thinking have been rapidly emerged. Organocatalysts, some of which are natural products, appear to solve the problems of metal catalysts. Compared to metal-based catalysis, they have many advantages including savings in cost, time, and energy, easier experimental procedure, and reduction of chemical waste. These benefits originate from the following factors. First, organocatalysts are generally stable in oxygen and water in the atmosphere, there is no need for special equipments or experimental techniques to operate under anhydrous or anaerobic conditions. Second, organic reagents are naturally available from biological materials as single enantiomers that they are easy and cheap to prepare which makes them suitable for small-scale to industrial-scale reactions. Third, in terms of safety related catalysis, small organic molecules are non-toxic and environmentally friendly. Therefore, the purpose of this research is to develop novel synthetic methods and design for various organocatalyst. Furthermore, it is expected that these organocatalysts can be applied to a variety of asymmetric reactions and study the transition state of these reactions using a metal sulface. Here, we report the synthesis of unprecedented organocatalysts, proline and pyrrolidine derivatives with quaternary carbon center.

• 공업화학
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• 제9권6호
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• pp.914-919
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• 1998

쉽게 얻을 수 있는 1,2:5,6-di-O-isopropylidene-D-mannitol (1)로부터 $C_2$-대칭성 피롤리딘 아미드 (8)을 합성하였다. 벤질 아민과 dimesylated hexitol (4)를 고리화 반응 시키면 트랜스 형태의 $C_2$-대칭성 피롤리딘 아민(5)가 주생성물로 얻어지나, 이와 함께 이성질화가 일어나 시스 이성질체인 화합물(6)도 생성된다. 피롤리딘 아민 (5,6)을 탈보호된 아민 (7)을 거쳐 아미드 (8,9)로 변형시켜 이를 순수한 형태로 분리하고, 이 $C_2$-대칭성 피롤리딘 아미드(8)의 광학 순도를 측정하기 위해 Mosher 유도체(13,14)를 합성하였다.$^1H$ 과$^{19}F$ NMR 실험으로 Mosher 유도체 (13,14)가 단일 물질임이 밝혀졌고, 이로서 피롤리딘 아미드 (8)이 광학적으로 순수한 화합물임을 확인하였다.

• Bulletin of the Korean Chemical Society
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• 제15권11호
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• pp.990-996
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• 1994

New ferrocene-based chelate amines, $Fe[C_5H_4CH(Me)NMe_2]_2\;(3), \;Fe[C_5H-3(CH(Me)NMe_2)(PPh_2)-1,2]_2\;(4),\;(C_5H_5)Fe(C_5H_3(CH_2NMe_2)(CH(CN)NMe_2-1,2)\;(6),\;and\;(C_5H_5)Fe(C_5H_3(CH_2NMe_2)(CH(Me)NMe_2-1,2)$ (7) have been prepared. The reaction and the coordination chemistry of 4 and other related compounds (S,R)-(1-N,N-dimethylaminoethyl)-2-dicyclohexylphosphino)ferrocene (CPFA) and 1,1'-bis-(diphenylphosphino)ferrocene (BPPF) with $Rh_2(OAc)_4(MeOH)_2$ were investigated. The reaction of the chiral ligand (S,R)-CPFA forms a complex of the type (${\eta}^1$-(S,R)-CPFA-P)$_2Rh_2(OAc)_4$ (8) in which the ligand is coordinated to both rhodium centers in a monodentate fashion through phosphorus. In contrast, the bisphosphine analogues such as BPPF and 4 afford chelate complexes of the type (${\eta}^2-PP)Rh_2(OAc)_4$ (9 & 10) where both ligands act as a chelate bidentate to a single rhodium atom. All these complexes were characterized by microanalytical and spectroscopic techniques. In one case, the structure of 8 was determined by X-ray crystallography. Crystals are monoclinic, space group C2 (No. 5), with a=26.389 (3), b=12.942 (1), c=11.825 (1) A, ${\beta}$=111.22(1)$^{\circ}$, V=3964.7 (8) $A^3$, Z=4, and $D_{calc}$=1.58 g $cm^{-3}$. Two Rh(II) centers are bridged by four $AcO^-$ groups in the ${\eta}^1$ : ${\eta}^1$ mode across a Rh-Rh single bond, and octahedral coordination at Rh(1) and Rh(1') is completed by axially coordinating (S,R)-CPFA and a briding $AcO^-$, respectively.