Elimination Reactions of Aryl Furylacetates Promoted by R2NH in MeCN: Effects of Base Solvent and β-Aryl Group on the Ketene-forming Transition State

Sang Yong Pyun; Kyu Cheol Paik; Man So Han; Byung Tae Kim; Bong Rae Cho

doi:10.1002/bkcs.11285

Elimination Reactions of Aryl Furylacetates Promoted by R₂NH in MeCN: Effects of Base Solvent and β-Aryl Group on the Ketene-forming Transition State

Sang Yong Pyun, Kyu Cheol Paik, Man So Han, Byung Tae Kim, Bong Rae Cho

* Honorary professors

Research output: Contribution to journal › Article › peer-review

Abstract

Ketene-forming elimination from C₄H₃(O)CH₂C(O)OC₆H₃-2-X-4-NO₂ (1) promoted by R₂NH in MeCN has been studied. The reactions produced elimination products and exhibited second-order kinetics with Brönsted β = 0.51, and |β_lg| = 0.47–0.53, indicating that the reaction proceeds by the E2 mechanism via an E2-central transition state. Comparison of β, |β_lg|, ΔH^≠, and ΔS^≠ values for R₂NH-promoted eliminations from ArCH₂C(O)OC₆H₃-2-X-4-NO₂ reveals that the transition-state structures for Ar = furyl and thienyl are similar and more symmetrical than that for Ar = Ph. This outcome has been attributed to the greater double bond stabilizing ability of the former than that of the latter.

Original language	English
Pages (from-to)	1306-1309
Number of pages	4
Journal	Bulletin of the Korean Chemical Society
Volume	38
Issue number	11
DOIs	https://doi.org/10.1002/bkcs.11285
Publication status	Published - 2017 Nov

Keywords

Base solvent
E2 mechanism
Elimination
Ketene
β-Aryl group

ASJC Scopus subject areas

Chemistry(all)

Access to Document

10.1002/bkcs.11285

Cite this

@article{4e30e2e5d52049b28941f148fd7cca55,

title = "Elimination Reactions of Aryl Furylacetates Promoted by R2NH in MeCN: Effects of Base Solvent and β-Aryl Group on the Ketene-forming Transition State",

abstract = "Ketene-forming elimination from C4H3(O)CH2C(O)OC6H3-2-X-4-NO2 (1) promoted by R2NH in MeCN has been studied. The reactions produced elimination products and exhibited second-order kinetics with Br{\"o}nsted β = 0.51, and |βlg| = 0.47–0.53, indicating that the reaction proceeds by the E2 mechanism via an E2-central transition state. Comparison of β, |βlg|, ΔH≠, and ΔS≠ values for R2NH-promoted eliminations from ArCH2C(O)OC6H3-2-X-4-NO2 reveals that the transition-state structures for Ar = furyl and thienyl are similar and more symmetrical than that for Ar = Ph. This outcome has been attributed to the greater double bond stabilizing ability of the former than that of the latter.",

keywords = "Base solvent, E2 mechanism, Elimination, Ketene, β-Aryl group",

author = "Pyun, {Sang Yong} and Paik, {Kyu Cheol} and Han, {Man So} and Kim, {Byung Tae} and Cho, {Bong Rae}",

note = "Funding Information: Acknowledgment. This work was supported by a Research Grant of Pukyong National University (2017).",

year = "2017",

month = nov,

doi = "10.1002/bkcs.11285",

language = "English",

volume = "38",

pages = "1306--1309",

journal = "Bulletin of the Korean Chemical Society",

issn = "0253-2964",

publisher = "Wiley-Blackwell",

number = "11",

}

TY - JOUR

T1 - Elimination Reactions of Aryl Furylacetates Promoted by R2NH in MeCN

T2 - Effects of Base Solvent and β-Aryl Group on the Ketene-forming Transition State

AU - Pyun, Sang Yong

AU - Paik, Kyu Cheol

AU - Han, Man So

AU - Kim, Byung Tae

AU - Cho, Bong Rae

N1 - Funding Information: Acknowledgment. This work was supported by a Research Grant of Pukyong National University (2017).

PY - 2017/11

Y1 - 2017/11

N2 - Ketene-forming elimination from C4H3(O)CH2C(O)OC6H3-2-X-4-NO2 (1) promoted by R2NH in MeCN has been studied. The reactions produced elimination products and exhibited second-order kinetics with Brönsted β = 0.51, and |βlg| = 0.47–0.53, indicating that the reaction proceeds by the E2 mechanism via an E2-central transition state. Comparison of β, |βlg|, ΔH≠, and ΔS≠ values for R2NH-promoted eliminations from ArCH2C(O)OC6H3-2-X-4-NO2 reveals that the transition-state structures for Ar = furyl and thienyl are similar and more symmetrical than that for Ar = Ph. This outcome has been attributed to the greater double bond stabilizing ability of the former than that of the latter.

AB - Ketene-forming elimination from C4H3(O)CH2C(O)OC6H3-2-X-4-NO2 (1) promoted by R2NH in MeCN has been studied. The reactions produced elimination products and exhibited second-order kinetics with Brönsted β = 0.51, and |βlg| = 0.47–0.53, indicating that the reaction proceeds by the E2 mechanism via an E2-central transition state. Comparison of β, |βlg|, ΔH≠, and ΔS≠ values for R2NH-promoted eliminations from ArCH2C(O)OC6H3-2-X-4-NO2 reveals that the transition-state structures for Ar = furyl and thienyl are similar and more symmetrical than that for Ar = Ph. This outcome has been attributed to the greater double bond stabilizing ability of the former than that of the latter.

KW - Base solvent

KW - E2 mechanism

KW - Elimination

KW - Ketene

KW - β-Aryl group

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