• Title/Summary/Keyword: Chiral auxiliaries

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Novel Asymmetric Synthesis of Unsaturated 1,2-Amino Alcohols

  • Kim, Ji-Duck;Jung, Young-Hoon
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.231.2-232
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    • 2002
  • The synthesis of chiral 1,2-amino alcohols has been an area of intense study in the synthetic and industrial fields, because of their important roles in organic synthesis as fundamental building blocks and their occurrence in a number of natural products. drugs. and chiral auxiliaries or ligands. General methods for the synthesis of these compounds can be divided into two large categories: functional group transformations and the C-C or the C-N bond formations. (omitted)

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Highly Diastereoselective Aldol-Type Reaction Using 3-Acetylthiazolidine-2-thione (3-아세틸티아졸리딘-2-티온을 이용한 입체선택적인 알돌-축합반응)

  • Tae Myeong Jeong;Ki Hun Park
    • Journal of the Korean Chemical Society
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    • v.33 no.4
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    • pp.426-430
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    • 1989
  • Amino alcohol-derived thiazolidinethiones [4-(S)-IPTT, 4(S)-ETT] serve as efficient chiral auxiliary in tin medicated aldol condensation. A highly enantioselective aldol-type reaction forming various ${\beta}$-hydroxy carbonyl compounds from 3-acetylthiazolidine-2-thione and achiral aldehyde is achieved via divalent tin enolate. The other advantages of these chiral auxiliaries were the ease of removal by methanolysis.

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Synthesis of Molecularly Imprinted Polymers for Chiral (S)-Ibuprofen and Their Molecular Recognition Mechanism (키랄(S)-이부푸로펜 함유 고분자의 합성과 제조된 고분자의 분자 인식 메카니즘)

  • Huangfu, Fengyun;Wang, Bing;Sun, Yan
    • Polymer(Korea)
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    • v.37 no.3
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    • pp.288-293
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    • 2013
  • A group of molecularly imprinted polymers (MIPs) with specific recognition for chiral (S)-ibuprofen were successfully prepared based on hydrogen bonds, utilizing ${\alpha}$-methacrylic acid as a functional monomer. The IR analysis of MIPs showed that the blue- and red-shifted hydrogen bonds were formed between templates and functional monomers in the process of self-assembly imprinting and re-recognition, respectively. According to UV-Vis analysis, we found that the ratio of host-guest complexes between template molecule and functional monomer was 1:1. The effect of cross-linker's quantity on the polymerization was studied by transmission electron microscope (TEM). The adsorption selectivity experiments indicated that MIPs exhibited higher selectivity to (S)-ibuprofen than those to ketoprofen and (R)-ibuprofen, (S)-ibuprofen's structural analogs.

Synthesis and Determination of Optical Purity of C2-Symmetric Pyrrolidine Amides as Chiral Auxiliaries (키랄 보조제로서의 C2-대칭성 피롤리딘 아미드의 합성과 광학 순도 결정)

  • Moon, Hong-sik;Koh, Dongsoo
    • Applied Chemistry for Engineering
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    • v.9 no.6
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    • pp.914-919
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    • 1998
  • Optically pure $C_2-Symmetric$ pyrrolidine amides (8) were synthesized from readily available 1,2:5,6-di-O-isopropylidene-D-mannitol (1). Cyclization of dimesylated hexitol (4) with benzyl amine gave an inseparable mixture of $C_2-Symmetric$ pyrrolidine amine derivative (5) as a major product, concurring with its cis isomer (6) as a minor product. The pyrrolidine amines (5,6) were converted to separable pyrrolidine amides (8,9) via free amine (7). Optical purity of desired $C_2-Symmetric$ pyrrolidine amide (8a) was determined with its Mosher derivatives (13,14) by their $^1H$ and $^{19}F$ NMR spectra.

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