• Title/Summary/Keyword: Addition reactions

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Reactions and Properties of Fullerene ($C_{60}$) (풀러렌의 성질과 반응)

  • Lim, Choong-Sun;Hong, Seong-Kyu;Ko, Weon-Bae
    • Elastomers and Composites
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    • v.45 no.2
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    • pp.74-79
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    • 2010
  • In this review, the properties of buckminsterfullerene and its organic and polymeric reactions were focused. In addition, polymer blending with $C_{60}$ will be briefly introduced. As soon as $C_{60}$ was discovered, chemists put their efforts to explore its reactivity with other compounds. The knowledge of the organic reactions with $C_{60}$ was extended to construct different types of fullerene polymers such as side chain fullerene polymers, main chain fullerene polymers, star shaped fullerene polymers, and dendritic fullerene polymers.

Regulation of Stereoselectivity and Reactivity in the Inter- and Intramolecular Allylic Transfer Reactions

  • Yu, Chan-Mo;Youn, Jin-soup;Jung, Hee-Keum
    • Bulletin of the Korean Chemical Society
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    • v.27 no.4
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    • pp.463-472
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    • 2006
  • The preparation of enatiomerically enriched homoallylic alcohols through asymmetric addition of chiral allylic transfer reagents and allylating reagents with chiral catalysts to the carbonyl functionalities represents an important chemical transformation. Excellent progress has been made over past decade in the development and application of catalytic asymmetric allylic transfer reactions. In this account, our efforts for the various intermolecular allylic transfer reactions such as allylation, propargylation, allenylation, and dienylation utilizing accelerating strategy and sequential allylic transfer reactions to achieve multiple stereoselection mainly using transition metal catalysts are described.

N-Substitution Reactions of 1-Substituted Tetrazoline-5-thiones

  • Kang, Han-Young;Cho, Yong-Seo;Lee, Won-Jae;Koh, Hun-Yeong;Chang, Moon-Ho
    • Bulletin of the Korean Chemical Society
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    • v.11 no.6
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    • pp.543-546
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    • 1990
  • N- vs. S-Substitution reactions of 1-substituted tetrazoline-5-thiones with various allyl or benzyl halides were studied in order to find effective conditions for N-substitution reactions. When allyl or benzyl halides were reacted with 1-substituted tetrazoline-5-thiones in the presence of TMSI or $BF_3{\cdot}OEt_2$ (or other Lewis acids), N-substitution at 4-position in addition to S-substitution occurred. Reactions were performed either with or without a solvent such as dioxane or propionitrile in the presence of potassium iodide.

Regio- and Stereoselective Reactions of (S)-(1-Methylpyrrolidin-2-yl)methyl Allyl Sulfide

  • Park, Ho-Koon;Baik, Nam-Hoon;Lee, Jae-Yeol;Kim, Soo-Ja;Ham, Won-Hoon
    • Archives of Pharmacal Research
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    • v.14 no.4
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    • pp.364-369
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    • 1991
  • The synthesis and regioselective reactions of a chiral allyl sulfide. (S)-(+)-(1-methylpyrrolidin-2-yl)methyl allyl sulfide (MAS, 1) are described. Remarkable ${\alpha}-regioselectivity$ was observed in the alkylation of the carbanion of MAS while 1:3 mixtures of ${\alpha}-and\;{\gamma}-adducts$ were produced in the addition of the MAS anion to aldehydes. However, a dramatic change of the regioselectivity was witnessed when Lewis acids such as $Et_3Al$, $Et_3B$, and $Ti(O^iPr)_4$ were used as additives in the addition reaction. In these cases, ${\alpha}-adducts$ were formed exclusively. A rationale for the change of regioselectivity is provided. And the stereochemical aspect of the addition reaction is also described.

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Synthesis of Nucleophilic Adducts of Thiols (Ⅴ). Addition of Thioglycolic Acid to $\omega,\;\omega$-Diacetylstyrene Derivatives

  • Huh, Tae-Sung;Han, Hae-Sook;Han, In-Sup;Kim, Tae-Rin
    • Bulletin of the Korean Chemical Society
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    • v.5 no.1
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    • pp.21-23
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    • 1984
  • The addition reactions of thioglycolic acid to ${\omega}$, ${\omega}$-diacetylstyrene derivatives were investigated. ${\omega}$, ${\omega}$-Diacetylstyrene derivatives easily undergo addition reactions with thioglycolic acid to form s-(2, 2-diacetyl-1-phenylethyl)-thiogycolic acid, s-[2,2-diacetyl-1-(methyl) phenylethyl]-thioglycolic acid, s-[2,2-diacetyl-1-(p-methoxy) phenylethyl]-thioglycolic acid and s-[2,2-diacetyl-1-(p-chloro) phenylethyl]-thioglycolic acid, respectively. The structures of these compounds were identified by neutralization equivalent, UV, IR, and NMR spectral data.

Kinetics and Mechanism of the Addition of Benzylamines to α-Cyano-β-phenylacrylamides in Acetonitrile

  • Oh, Hyuck-Keun;Ku, Myoung-Hwa;Lee, Hai-Whang
    • Bulletin of the Korean Chemical Society
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    • v.26 no.6
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    • pp.935-938
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    • 2005
  • Nucleophilic addition reactions of benzylamines (BA; $XC_6H_4CH_2NH_2$) to $\alpha-cyano-\beta$-phenylacrylamides (CPA; $YC_6H_4CH=C(CN)CONH_2$) have been investigated in acetonitrile at 25.0 ${^{\circ}C}$. The rate is first order with respect to BA and CPA and no base catalysis is observed. The addition of BA to CPA occurs in a single step in which the addition of BA to $C_{\beta}$ of CPA and proton transfer from BA to $C_{\alpha}$ of CPA take place concurrently with a four-membered cyclic transition state structure. The magnitude of the Hammett ($\rho_X$) and Bronsted ($\beta_X$) coefficients are rather small suggesting an early tansition state (TS). The sign and magnitude of the crossinteraction constant, $\rho_XY$ (= −D0.26), is comparable to those found in the normal bond formation processes in the $S_N2$ and addition reactions. The normal kinetic isotope effect ($k_H/k_D\;{\gt}$ 1.0) and relatively low ${\Delta}H^{\neq}$ and large negative ${\Delta}S^{\neq}$ values are also consistent with the mechanism proposed.

Integrated Reporting Disclosure and Its Implications on Investor Reactions

  • ULUPUI, I Gusti Ketut Agung;MURDAYANTI, Yunika;YUSUF, Muhammad;PAHALA, Indra;ZAKARIA, Adam
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.12
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    • pp.433-444
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    • 2020
  • The purpose of this study is to analyze integrated reporting disclosure and its implications on investor reactions. The population in this study is all manufacturing companies listed on the Indonesia stock exchange from 2017 to 2019, totaling 171 companies, and the sampling technique used is purposive sampling method. The method used in this research is a quantitative description using the financial statements of manufacturing companies listed on the Indonesia stock exchange. The data analysis method used is multiple regression analysis with intervening variables using AMOS 24 software. The results of this study show a positive and significant effect of profitability (X1) and company size (X2) on integrated reporting (IR); a positive and insignificant effect of stakeholder pressure (X3) on integrated reporting (IR); a positive and significant effect of profitability (X1) and stakeholder pressure (X3) on investor reactions (Y); a positive and insignificant effect of firm size (X2) and integrated reporting (IR) on investor reactions (Y). Suggestions are that in further studies, we can increase the sample size by including other industries, and in addition to using annual reporting, we can also use other sources such as websites, press releases, and prospectuses to improve the robustness of this study by relying on other data sources.