Unveiling the high reactivity of benzyne in the formal [3+2] cycloaddition reactions towards thioamides through the Molecular Electron Density Theory

被引：9

作者：

Rhyman, Lydia ^{[1
,2
]}

Rios-Gutierrez, Mar ^{[3
,4
]}

Domingo, Luis R. ^{[3
]}

Ramasami, Ponnadurai ^{[1
,2
]}

机构：

[1] Univ Mauritius, Fac Sci, Dept Chem, Reduit 80837, Mauritius

[2] Univ Johannesburg, Dept Chem Sci, ZA-2028 Johannesburg, South Africa

[3] Univ Valencia, Dept Organ Chem, Dr Moliner 50, E-46100 Valencia, Spain

[4] McMaster Univ, Dept Chem & Chem Biol, 1280 Main St West, Hamilton, ON L85 4L8, Canada

来源：

TETRAHEDRON | 2020年 / 76卷 / 39期

基金：

欧盟地平线“2020”;

关键词：

AB-INITIO; POLAR CYCLOADDITION; ELECTROPHILICITY; CYCLOALKYNES; LOCALIZATION; MODEL; IMPLEMENTATION; OPTIMIZATION; CONSERVATION; CYCLOPENTYNE;

D O I：

10.1016/j.tet.2020.131458

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The domino reaction of benzyne with thioamide has been studied within the Molecular Electron Density Theory (MEDT) at the MPWB1K/6-311G(d) level. This domino reaction takes place through i) a formal [3 + 2] cycloaddition (32CA) reaction affording an ammonium ylide, and ii) an extrusion of ethylene from this species yielding a dihydrothiazole. Topological analysis of the electron density of benzyne shows its pseudodiradical structure, that is, without any energy cost, changes to a carbenoid one, allowing its participation as electrophile in polar reactions. As a consequence, the formal 32CA reaction does not have an activation enthalpy. Analysis of the changes of electron density along the domino reaction indicates that while the formal 32CA reaction takes place through a two-stage one-step mechanism, the extrusion of ethylene takes place through an intramolecular E2 elimination mechanism. The present MEDT study reveals the chameleonic structure/reactivity of benzyne, allowing its participation in both non-polar and polar reaction with an unappreciable activation enthalpy. (C) 2020 Elsevier Ltd. All rights reserved.

引用

页数：10

共 73 条

[1]

Ahrens J., 2005, VIS HDB, DOI 10.1016/B978-012387582-2/50038-1

[2]

[Anonymous], 2005, P 2005 LINUX CLUSTER

[3]

[Anonymous], 1988, CHEM REV

[4]

[Anonymous], EUR J ORG CHEM

[5]

Ayachit U, 2015, The ParaView Guide: Updated for ParaView Version 4.3

[6] The reaction of cyclopentyne with ethene: Concerted vs stepwise mechanism? [J].

Bachrach, SM ;

Gilbert, JC .

JOURNAL OF ORGANIC CHEMISTRY, 2004, 69 (19) :6357-6364

[7] DFT study of the cycloaddition reactions of strained alkynes [J].

Bachrach, SM ;

Gilbert, JC ;

Laird, DW .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2001, 123 (27) :6706-6707

[8]

Bader R. F. W., 1994, International Series of Monographs on Chemistry

[9] THE CHARACTERIZATION OF ATOMIC INTERACTIONS [J].

BADER, RFW ;

ESSEN, H .

JOURNAL OF CHEMICAL PHYSICS, 1984, 80 (05) :1943-1960

[10]

Balci M, 2000, ADV STR INT ORG MOL, V8, P43

← 1 2 3 4 5 6 7 8 →