• Title/Summary/Keyword: phosphine

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Electron-Beam Mediated Rearrangement and Fragmentation of Bis(diphenylphosphino)alkane Derivatives in Gas Phase

  • Jeon, Yea-Sel;Choi, Jeong Chul;Jeong, Young-Sik;Hwang, Kwang-Jin
    • Rapid Communication in Photoscience
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    • v.2 no.1
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    • pp.31-33
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    • 2013
  • The irradiation of electron-beam onto bis-(diphenylphosphino)methane, ethane, propane and butane initiated phenyl-shift from a phosphine to another phosphine atom and subsequent fragmentation resulted in the formation of triphenylphosphine derivative as key intermediate. The mechanism of those processes is speculated.

Tris(2-methoxyphenyl)phosphine as a Highly Active Ligand for the Synthesis of Biaryls by Suzuki Coupling Reaction

  • Kang, Pill-Seong;Ko, Sung-Bo;Ko, Jang-Myoun;Park, Jeong-Ho
    • Bulletin of the Korean Chemical Society
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    • v.30 no.11
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    • pp.2697-2700
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    • 2009
  • A $Pd(OAc)_2/(o-MeOPh)_3P$ system has been developed for the catalytic Suzuki coupling of aryl bromides with arylboronic acids. Our catalyst system covers a broad spectrum of commonly available arylboronic acids and aryl bromides to provide biaryls in very good yields. The catalyst system works very well in the synthesis of sterically hindered biaryls.

Kinetics of the Photochemically Generated t-Butoxy Radical Reactions with Phosphine(PH$_3)^*$

  • Park Chan Ryang;Choo Kwang Yul
    • Bulletin of the Korean Chemical Society
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    • v.6 no.4
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    • pp.206-209
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    • 1985
  • The gas phase reactions of the photochemically generated t-butoxy radicals with phosphine ($PH_3$) were studied in the temperature range of $35-80^{\circ}C.$ We found the significant differences between high temperature thermal reactions and low temperature photo reactions. In comparison with the reactions of t-butoxy radicals with other hydrogen donors, some possible mechanistic suggestions were made for the explanation of the results.

Enhanced Interfacial Adhesion of Carbon Fibers by Poly (arylene ether phosphine oxide) Coatings (Poly(arylene ether phosphine oxide) 코팅에 의한 탄소섬유의 계면 접착성 향상 연구)

  • 김익천;강현민;육종일;윤태호
    • Composites Research
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    • v.12 no.4
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    • pp.55-61
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    • 1999
  • Interfacial shear strength (IFSS) of poly(arylene ether phosphine oxide) (PEPO) coated carbon fibers was evaluated via microdroplet test and compared with results obtained from carbon fibers coated with poly(arylene ether sulfone) (PES), Udel$^{\circledR}$ P-1700 and Ultem$^{\circledR}$ 1000. Interfacial adhesion between thermoplastics and uncoated carbon fibers was also measured in order to understand the adheion mechanism. PEPO coated carbon fibers showed the highest IFSS, followed by PES, Udel and Ultem coated fibers. A similar trend was observed for thermoplastic/uncoated fibers. SEM analysis indicated that only PEPO coated fiber exhibited cohesie failure in the vinylester resin, while others showed failure at or near the interface of polymer coating and vinylester resin. The enhanced interfacial adhesion by PEPO coating could be attributed to the strong interaction of P = 0 moiety to the fiber as well as to the vinylester resin.

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Monitoring of Aluminium Phosphide Residues in Wheat and Wheat Flour (밀과 밀가루 중 알루미늄포스파이드 잔류량 모니터링)

  • Choi, Yong-Hoon;Yoon, Sang-Hyeon;Hong, Hye-Mi;Kang, Yun-Sook;Chae, Kab-Ryong;Lee, Jong-Ok
    • Korean Journal of Food Science and Technology
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    • v.37 no.4
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    • pp.532-536
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    • 2005
  • GC-NPD analysis was performed on residues of aluminium phosphide in raw wheat and wheat products by trapping gaseous phosphine in the headspace of vessel. In Australian wheat, over 95% of samples were detected below 1 ppb, considered as safe level, whereas in American wheat, about 70% of 58 samples were detected within 1-10 ppb with 4 showing over 10 ppb. About 14-22% phosphine residues of raw wheat were retained after milling process. Wheat samples of same origin showed significant varying levels of phosphine.

A Case of Aluminum Phosphide Poisoning (알루미늄 포스파이드 중독 1례)

  • Jung, Hyun-Min;Kim, Ji-Hye;Paik, Jin-Hui;Kim, Jun-Sig;Kim, Jung-Hun;Han, Seung-Baik
    • Journal of The Korean Society of Clinical Toxicology
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    • v.9 no.2
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    • pp.109-112
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    • 2011
  • Aluminum phosphide is commonly used as a rodenticidal agent in agricultural workplaces. However, reported cases of aluminum phosphide poisoning in Korea are rare. Upon contact with moisture in the air, aluminum phosphide releases highly toxic phosphine gas ($PH_3$). $PH_3$ is readily absorbed through lung epithelium and into the bloodstream. Phosphine may cause denaturing of oxyhemoglobin and enzymes important to respiration and metabolism, and also may effect cellular membranes. There are numerous complications associated with acute aluminum phosphide poisoning including gastrointestinal, respiratory, and cardiac toxicities. We report the case of a 46-year-old man who suffered from respiratory and cardiac toxicities after unintentional aluminum phosphide exposure. More intensive education for prevention is recommended.

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Structure and Properties of a Nonheme Pentacoordinate Iron(II) Complex with a Macrocyclic Triazapyridinophane Ligand

  • You, Minyoung;Seo, Mi Sook;Kim, Kwan Mook;Nam, Wonwoo;Kim, Jinheung
    • Bulletin of the Korean Chemical Society
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    • v.27 no.8
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    • pp.1140-1144
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    • 2006
  • A macrocyclic ligand, N,N',N'-tribenzyl-2,11,20-triaza[3,3,3](2,6)pyridinophane (BAPP), was used to prepare an iron(II) complex as a nonheme model complex, $[(BAPP)Fe]^{+2}$ (1). X-ray crystallography of a colorless crystal of 1 revealed that BAPP acted as a pentadentate ligand due to geometrical strain for the formation of a six-coordinate iron(II) complex by BAPP. As a result, the iron center revealed a significantly distorted square pyramidal geometry similar to that found in the active site of taurine dioxygenase (tauD). In the reaction of 1 with PhIO, no intermediate was observed in the UV-visible region of spectrometer at low temperatures. Catalytic oxidations of triphenyl phosphine with PhIO at ${-40^{\circ}C}$ revealed that 1 was able to convert triphenyl phosphine to triphenyl phosphine oxide.23; SSOCHKThioanisole was also oxidized to the corresponding methylphenyl sulfoxide under the same conditions.

Design, Synthesis and Preliminary Biological Evaluation of a Biotin-S-S-Phosphine Reagent

  • Kang, Dong W.;Kim, Eun J.
    • Bulletin of the Korean Chemical Society
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    • v.35 no.2
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    • pp.383-391
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    • 2014
  • Biotin-S-S-Phosphine was designed and synthesized as a potential tool for a proteomic study of O-GlcNAcmodified proteins. This reagent features a disulfide linker between a triarylphosphine moiety, which allows selective conjugation to azide-containing proteins, and a biotin moiety that can allow easy isolation through its strong affinity toward avidin-coated solid beads. The disulfide linkage within this reagent can allow the easy release of the bound molecules of interest, which is difficult to achieve when a biotin:avidin pair is used alone, by reducing the disulfide bond of the reagent with DTT. Preliminary in vitro biological assays with azidelabeled and unlabeled cell lysates and a pure protein Nup62 showed that the Biotin-S-S-Phosphine reagent is highly reactive toward the free thiol groups of proteins. When a molecular tool with a disulfide linker is applied to the enrichment of the molecules of interest from other species, it is important to block the free-thiols of the sample using exhaustive alkylation prior to the Staudinger ligation reactions to restore the bioorthogonal nature of this reaction.

Comparative Effects of Gamma Irradiation and Phosphine Fumigation on Lipid-Related Components of White Ginseng During Post-Treatment Period (감마선과 Phosphine 처리가 백삼의 지방질 관련 성분에 미치는 영향)

  • Kwon, Joong-Ho;Lee, Jung-Eun;Jeong, Seong-Weon;Choi, Kang-Ju
    • Korean Journal of Food Science and Technology
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    • v.31 no.6
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    • pp.1447-1452
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    • 1999
  • Lipid-related components were comparatively investigated for white ginseng when exposed to both phosphine fumigation and gamma irradiation at 5 kGy or less, which were found effective for improving its biological quality. Fumigation resulted in the increase in pH of the sample, and thereafter it showed a decreasing tendency in all samples during storage for 6 months at ambient $(20^{circ}C/70%\;RH)$ and accelerated $(40^{\circ}C/90%\;RH)$ conditions. The severe conditions led to an apparent browning of the stored samples without significant differences among them, while the sample stored at ambient condition showed negligible changes in its color up to 6 months. The development of browning in the stored sample was in proportional to hydrogen donating ability of the corresponding sample extract. TBA value increased by gamma irradiation gradually decreased with storage time, showing similar values to that of other samples, whereas carbonyl value gradually increased in all samples. Both fumigation and gamma irradiation caused negligible changes in fatty acid composition; however, a partial increase in saturated fatty acid composition and some decrease in polyunsaturated ones were observed with the storage time.

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