• 제목/요약/키워드: Acetic anhydride

검색결과 108건 처리시간 0.021초

아세칠화 WPC 이중개질처리에 의한 전통창호 소나무재의 물성 개선 (Wood Modification of Pinus densiflora Sieb, et Zucc. for korean traditional latticework by combined treatment of Acetylation followed by Styren-Methyl metacrylate impregnation)

  • 이화형;이민경
    • 한국가구학회지
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    • 제14권1호
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    • pp.11-20
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    • 2003
  • Wood cell-wall modification with acetic anhydride, lumen filled with styren monomer and methyl methacrylate, and a combination of these two treatments were studied for their effectiveness for dimensional stability. Compared to those of untreated Pinus densiflora Sieb. et Zucc and sole acetylated red pine, The combination of acetylation and impregnation with methy methacrylate greatly reduced water absorption, increased ASE to the best and gave better bending strength and compression strength.

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Synthesis and Reactions of Some Pyridazine Derivatives

  • A, Khalifa-Fathy
    • Archives of Pharmacal Research
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    • 제13권2호
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    • pp.198-200
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    • 1990
  • 3, 4-Diphenyl-5-cyanopyridazin-6-one 3 was prepared from the reaction of cyano acetamide 2 with benzihydrazone in dry pyridine. A series of its derivatives was prepard. Tolyl and benene sulphonyl derivatives 6a and 6b are also prepared. 3, 4-Diphenyl-5-cyanopyridazin-6-thione 5 was obtained from 3 by the action of $P_2S_5$ while 3, 4 diphenyl-5-cyano 6-chloropyridazine 4 was obtained from 3 by the action POCl$_3$. The reaction of 4 with hydrazine hydrate directly afforded the pyrazolopyridazine derivative 7. Compound 4 also reacted with phenylhydrazine, aniline, thiophenol and anthranilic acid to yield pyridazine derivatives 8, 9, 10 and 11, respectively. On treatment of compound 11 with acetic anhydride it cyclised to afford pyridazino pyrimidine derivatives 12.

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Very Efficient and Rapid Catalyst-free One-pot Three Component Synthesis of 2,5-Dihydro-5-imino-2-methylfuran-3,4-dicarboxylate Derivatives Under Ultrasound Irradiation

  • Rouhani, Morteza;Ramazani, Ali;Joo, Sang Woo;Hanifehpour, Younes
    • Bulletin of the Korean Chemical Society
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    • 제33권12호
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    • pp.4127-4130
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    • 2012
  • We report a fast, efficient, and facile route for the synthesis of 2,5-dihydro-5-imino-2-methylfuran-3,4-dicarboxylate derivatives from the isocyanide, dialkyl acetylenedicarboxylate and acetic anhydride under ultrasound-assisted conditions. Utilization of easy reaction conditions, very high to excellent yields, and short reaction times makes this manipulation potentially very useful.

친환경 촉매 Iron (III) phosphate: 실온/무용매 반응조건에서 알코올과 페놀의 선택적인 아실화 반응 (Iron (III) Phosphate as a Green and Reusable Catalyst Promoted Chemo Selective Acetylation of Alcohols and Phenols with Acetic Anhydride Under Solvent Free Conditions at Room Temperature)

  • Behbahani, F.K.;Farahani, M.;Oskooie, H.A.
    • 대한화학회지
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    • 제55권4호
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    • pp.633-637
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    • 2011
  • 알코올과 페놀 계 화합물을 아실화시키는 반응에서, iron (III) phosphate 촉매를 사용했을 때에, 좋은 수율로 아실화 화합물을 얻었다. Iron (III) phosphate 촉매는 또한 친환경 반응에 재사용할 수 있는 친환경 촉매이다.

새로운 비스-크라운 에테르의 합성(제 2보) : 실옥산 사슬에 연결된 비스-크라운 에테르 (Synthesis of New Bis-Crown Ether (Ⅱ) : Bis-Crown Ether with Siloxane Moiety)

  • 장승현;김재용;정광보
    • 대한화학회지
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    • 제40권9호
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    • pp.635-639
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    • 1996
  • 실옥산 사슬에 크라운 에테르가 연결된 유연성이 큰 새로운 비스-크라운 에테르를 합성하였다. 1, 3-Bis(trimethylsiloxy)-1, 3-dimethyl-1, 3-di(4'-ethylbenz-o-18-crown-6) disiloxane(1)은 백금촉매 존재하에서 1, 3-bis(trimethylsiloxy)-1, 3-dimethyl-1, 3-disiloxane과 4'-vinylbenzo-18-crown-6의 반응에 의해 합성하였다.

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아세틸화 처리가 대나무재의 초음파 전달 속도에 미치는 영향 (Effect of Acetylation on Ultrasonic Velocity of Bamboo)

  • 강호양;이관영
    • Journal of the Korean Wood Science and Technology
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    • 제25권3호
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    • pp.8-15
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    • 1997
  • The ultrasonic velocity and dynamic MOE of acetylated bamboos were investigated using PUNDIT, a transit time measuring device for longitudinal ultrasonic propagation. Bamboo specimens were boiled in acetic anhydride for 2, 4 and 6 hours, and the maximum average WPG (Weight Percentage Gain) of 19% was obtained at 6 hours. The volumes of acetylated bamboos increase with boiling time and WPG, while as WPG increases their oven-dry densities generally increase with a concave around 5% WPG. This oven-dry density pattern likely influences the trends of ultrasonic velocity and dynamic MOE. which generally decrease with a convex around 5% WPG. It is postulated that during boiling extractives in a bamboo move and aggregate at its surfaces transiently, resulting in the increase of ultrasonic velocity and dynamic MOE. To explain the fact that ultrasonic velocity varies with WPG a simple model was proposed and some ultrasonic properties of a transmitted wave were examined.

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Synthesis and X-ray Crystallographic Characterization of p-Diacetylcalix[4]arene

  • Young Ja Park;Kwanghyun No;Jung Mi Shin
    • Bulletin of the Korean Chemical Society
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    • 제12권5호
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    • pp.525-529
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    • 1991
  • A simple route is described for the selective functionalization of calixarene at the para positions of phenyl rings. Calix[4]arene tetraacetate 2, obtained from the treatment of calix[4]arene with acetic anhydride, undergoes Fries rearrangement to yield the diametrically para substituted p-diacetylcalix[4]arene 3 in 80% yield. The crystal and molecular strucutre has been determined by X-ray diffraction method. The crystals are orthorhombic, space group Pna21, with a = 11.121 (3), b = 10.374 (3), c = 21.690 (6) $\AA$ and Z = 4. The structure was solved by direct method and refined by full-matrix least-squares methods to final R of 0.036 for 1795 observed reflections. Each hydroxyl hydrogen atom is disordered over two positions. The macrocycle exists in the cone conformation which is determined by the strong circular intramolecular flip-flop type hydrogen bonds of phenolic OH, while crystal packing effects of the diametrically para-acetyl substituents seem to be responsible for the distortion of the cone conformation.

Synthesis and Biological Investigations of New Thiazolidinone and Oxadiazoline Coumarin Derivatives

  • Abd Elhafez, Omaima Mohamed;El Khrisy, Ezz El Din Ahmed Mohamed;Badria, Farid;Fathy, Alaa El Din Mohamed
    • Archives of Pharmacal Research
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    • 제26권9호
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    • pp.686-696
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    • 2003
  • Ethyl (coumarin-4-oxy)acetate 1 was prepared through the reaction of 4-hydroxycoumarin with ethyl bromoacetate. Compound 1 was allowed to react with hydrazine hydrate to produce coumarin-4-oxyacetic hydrazide 2. The synthesis of N-(arylidene and alkylidene)-coumarin-4-oxyacetic hydrazones 3-20 was performed. The preparation of 2-substituted-3-[(coumarin-4-oxy) acetamido]thiazolidinones 21-26 and 2-[(coumarin-4-oxy )methyl]-4-acetyl-5-substituted-$\Delta^2$-1,3,4-oxadiazolines 27-33 was performed by the reaction of the hydrazones 3, 4, 7, 9, 12, 14 with mercaptoacetic acid and the hydrazones 3, 4, 5, 7, 12, 15, 16 with acetic anhydride, respectively. The antiviral activities, cytotoxicities and structure-activity relationship (SAR) towards different microorganisms of the prepared compounds were studied.

O-Acylation of Heteropolyanions Containing Two Adjacent Vanadium Atoms

  • Lee, Chul-Wee;So, Hyun-Soo;Lee, Kyu-Ryong
    • Bulletin of the Korean Chemical Society
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    • 제9권6호
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    • pp.362-364
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    • 1988
  • Reaction of Keggin- or Dawson-type heteropolyanions containing two adjacent vanadium atoms with acetic anhydride in the presence of acid produced acylated anions. Heteropolyanions with one or no vanadium atom do not react under the same conditions, indicating that the acyl group is attached to the bridging oxygen atom between the two vanadium atoms. A characteristic infrared band at 1760 $cm^{-1}$ was observed for the acylated anions. The 8-line EPR spectrum shows that one of the vanadium atoms is reduced to V(IV ). The acylated heteropolyanions are easily hydrolyzed, and its acyl group can also be transferred to aniline.

Studies on Synthesis and Heterocyclisation Reactions of Michael Products and Formation of New 1, 4-Thiazine Quinoxaline Derivatives

  • Mahgoub, S.A.
    • Archives of Pharmacal Research
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    • 제13권4호
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    • pp.319-324
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    • 1990
  • Synthesis of $\alpha$-piperidino and $\alpha$-morphelino styryl quinoxalinone 2f, 2g respectively by facile one step method is reported. The Michael adducts (3a-d) obtained by the interaction of 2-styryl-2 (1H) quinoxalinone (2) and ethylacetoacetate have been treated with resorcino and hydroxylamine separately. With resorcinol the chromones (4) are obtained whereas with ydroxylamine isoxazoles (6) are the products. Michael addition of acetylacetone to 2 leads to 3-[1'-aryl-2'-(2'-hydroxy-3'-quinoxalinyl)ethyl]-2, 4-pentanediones (5) which undergo cyclisation with hydroxylamine to give isoxazoles (7). Addition of thiopenol and thioglycolic acid to 2 gives 3-$\alpha$[$\beta$-(phenyl)-$\beta$-(plenylthio)]ethyl-2(1H)-quinoxalinone (8) and 3-$\alpha$-[$\beta$-phenyl)-$\beta$-(hydroxycarbonylmethylithio)]-ethyl-2(1H)-qui noxalinone (9) respectively. 2-Bromomethyl-2(1H)-quinoxalinone (1b) reacts with thioglycolic acid to gives S-[2 (1H)-oxoquionoxaline-3-yl-methyl] mercaptoacetic acid (10) which on cyclisation with acetic anhydride/pyridine affords 1, 2, 5, 6-tetrahydro [1, 4]thiazino[4, 3-a] quinoxaline-1, 6-dione (11).

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