• 제목/요약/키워드: Diethylzinc

검색결과 48건 처리시간 0.019초

Chiral β-Amino Thiol Catalysts for the Enantioselective Addition of Diethylzinc to Aldehydes

  • 강자효;김정환;이준원;김동수;김주인
    • Bulletin of the Korean Chemical Society
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    • 제17권12호
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    • pp.1135-1142
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    • 1996
  • Reaction of diethylzinc with α-branched aldehydes in the presence of a catalytic amount (5 mol %) of various β-amino thiols in toluene or ether provided the corresponding secondary alcohols in outstanding ee. Detailed preparative procedure for the β-amino thiols are presented.

Diethylzinc를 사용하여 PECVD로 증착한 ZnO 박막의 미세 구조 분석 (Microstructure of ZnO Thin Films Deposited by PECVD using Diethylzine)

  • 김영진;김형준
    • 한국결정학회지
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    • 제4권2호
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    • pp.92-99
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    • 1993
  • Diethylzinc를 사용하여 PECVD장치로 ZnO 박막을 증 착하여 미세구조를 분석하였다. 기판 온도 100℃에서부터 이미 미세 결정 입자로 구성된 ZnO 박막의 증착이 가능했으며, 200℃이상에서는 C 축 배향성이 뛰어난 ZnO 박막이 유리 기판위에 증착되었다. c-면 사파이어 기판위에 증착된 ZnO 박막을 TEM으로 분석한 결과 기판 온도 350℃에서 EPITAXIAL (002) ZnO 박막이 성장됐으며, 입계에서는 Moire패턴에 의한 dislocation이 관찰되었다.

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Highly Enantioselective Addition of Diethylzinc to Aldehydes Catalyzed by Novel Chiral tert-Amino Alcohols

  • Zhang, Cong-Hai;Yan, Sheng-Jiao;Pan, Sheng-Qiang;Huang, Rong;Lin, Jun
    • Bulletin of the Korean Chemical Society
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    • 제31권4호
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    • pp.869-873
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    • 2010
  • A series of novel chiral tert-amino alcohols 4a-h derived from enantiomerically pure phenylalanine were synthesized efficiently and used as chiral ligands in the catalytic enantioselective ethylation of aldehydes with diethylzinc (diethylzinc-to-aldehyde addition). The use of 10 mol % of the amino alcohols led to the corresponding sec-alcohols with excellent enantioselectivities (up to 100% ee) and high yields.

Investigation on Reaction Pathways for ZnO Formation from Diethylzinc and Water during Chemical Vapor Deposition

  • Kim, Young-Seok;Won, Yong-Sun
    • Bulletin of the Korean Chemical Society
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    • 제30권7호
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    • pp.1573-1578
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    • 2009
  • A computational study of the reactions between Zn-containing species, the products of the thermal decomposition of diethylzinc (DEZn) and water was investigated. The Zn-containing species – $C_2H_5)_2,\;HZnC_2H_5,\;and\;(ZnC_2H_5)_2$ – were assumed to react with water during ZnO metal organic chemical vapor deposition (MOCVD). Density functional theory (DFT) calculations at the level of B3LYP/6-311G(d) were employed for the geometry optimization and thermodynamic property evaluation. As a result dihydroxozinc, $Zn(OH)_2$, was the most probable reaction product common for all three Zn-containing species. A further clustering of $Zn(OH)_2$ was investigated to understand the initial stage of ZnO film deposition. In experiments, the reactions of DEZn and water were examined by in-situ Raman scattering in a specially designed MOCVD reactor. Although direct evidence of $Zn(OH)_2$ was not observed, some relevant reaction intermediates were successfully detected to support the validity of the gas phase reaction pathways proposed in the computational study.