A mechanistic rationale for the mode selectivity in the intramolecular Cyclization of ethylene-tethered iminoketenimines:: [2+2] versus [4+2] stepwise cycloadditions

被引：10

作者：

Alajarín, M ^{[1
]}

Sánchez-Andrada, P ^{[1
]}

Vidal, A ^{[1
]}

Tovar, F ^{[1
]}

机构：

[1] Univ Murcia, Fac Quim, Dept Quim Organ, E-30100 Murcia, Spain

来源：

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY | 2004年 / 2004卷 / 12期

关键词：

ab initio and density functional; calculations; cumulenes; cycloaddition; reaction mechanisms; Schiff bases;

D O I：

10.1002/ejoc.200400093

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

A stepwise mechanism, via a zwitterionic intermediate, has been established by ab initio and DFT calculations for the intramolecular cyclization of N-(3-azabut-3-enyl)ketenimine into its corresponding [2+2] cycloadduct. The control of the mode selectivity ([2+2] versus [4+2] cycloaddition) in the intramolecular cyclization of C-vinyl-N-(iminoethylene)ketenimines, which favors the [4+2] cycloadducts, also has been rationalized by comparing the energies calculated for both reaction pathways; the results have been confirmed by a quantitative kinetic analysis. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).

引用

页码：2636 / 2643

页数：8

共 43 条

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