94238-23-0Relevant academic research and scientific papers
Relative Rates of Metal-Free Azide-Alkyne Cycloadditions: Tunability over 3 Orders of Magnitude
Skelly, Patrick W.,Sae-Jew, Jirapon,Kitos Vasconcelos, Ana Paula,Tasnim, Jerin,Li, Longbo,Raskatov, Jevgenij A.,Braslau, Rebecca
, (2019/10/14)
The thermal (3 + 2) dipolar azide-alkyne cycloaddition, proceeding without copper or strained alkynes, is an underutilized ligation with potential applications in materials, bioorganic, and synthetic chemistry. Herein, we investigate the effects of alkyne substitution on the rate of this reaction, both experimentally and computationally. Electron-withdrawing groups accelerate the reaction, providing a range of relative rates from 1.0 to 2100 between the slowest and fastest alkynes studied. Unexpectedly, aryl groups conjugated to the alkyne significantly retard the reaction rate. In contrast, a sulfonyl, ester-substituted alkyne is reactive enough that it couples with an azide at room temperature in a few hours. This reactivity scale should provide a guide to those who wish to use this ligation under mild conditions.
Relative Rates of Metal-Free Azide-Alkyne Cycloadditions: Tunability over 3 Orders of Magnitude
Skelly, Patrick W.,Sae-Jew, Jirapon,Kitos Vasconcelos, Ana Paula,Tasnim, Jerin,Li, Longbo,Raskatov, Jevgenij A.,Braslau, Rebecca
, p. 13615 - 13623 (2019/11/14)
The thermal (3 + 2) dipolar azide-alkyne cycloaddition, proceeding without copper or strained alkynes, is an underutilized ligation with potential applications in materials, bioorganic, and synthetic chemistry. Herein, we investigate the effects of alkyne substitution on the rate of this reaction, both experimentally and computationally. Electron-withdrawing groups accelerate the reaction, providing a range of relative rates from 1.0 to 2100 between the slowest and fastest alkynes studied. Unexpectedly, aryl groups conjugated to the alkyne significantly retard the reaction rate. In contrast, a sulfonyl, ester-substituted alkyne is reactive enough that it couples with an azide at room temperature in a few hours. This reactivity scale should provide a guide to those who wish to use this ligation under mild conditions.
Hypervalent iodine(iii)-induced oxidative [4+2] annulation of o-phenylenediamines and electron-deficient alkynes: Direct synthesis of quinoxalines from alkyne substrates under metal-free conditions
Okumura, Sota,Takeda, Youhei,Kiyokawa, Kensuke,Minakata, Satoshi
, p. 9266 - 9268 (2013/10/01)
Hypervalent iodine(iii)-induced oxidative [4+2] annulation of o-phenylenediamines and electron-deficient alkynes under metal-free conditions has been developed. The reaction allows for direct access to quinoxalines bearing two electron-withdrawing groups in an efficient manner.
Sulphonomercuriation route to vinyl and ethynyl sulphones
Rajakumar, Perumal,Kannan, Arunachalam
, p. 154 - 155 (2007/10/02)
Ethynyl sulphones were obtained from the reaction of substituted acetylenes with mercury(II) chloride and sodium benzenesulphinate followed by oxidative demercuriation.
