A theoretical study of aromaticity in squaramide and oxocarbons

被引：90

作者：

Quiñonero, D ^{[1
]}

Frontera, A ^{[1
]}

Ballester, P ^{[1
]}

Deyá, PM ^{[1
]}

机构：

[1] Univ Illes Balears, Dept Quim, E-07071 Palma de Mallorca, Spain

来源：

TETRAHEDRON LETTERS | 2000年 / 41卷 / 12期

关键词：

oxocarbon acids and derivatives; aromaticity; NMR; theoretical studies;

D O I：

10.1016/S0040-4039(00)00084-8

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

A systematic estimation of aromaticity in oxocarbon acids, their dianions, squaramide and its complex with the ammonium cation have been studied using structural and magnetic criteria. Results based on Nucleus Independent Chemical Shift (NICS) predict that deltic and squaric acids and their dianions are aromatic, while croconic and rhodizonic acids and their dianions are non-aromatic. Squaramide is less aromatic than its complex with the ammonium cation. Therefore, the gain in aromaticity in the squaramide ring is a possible explanation for the remarkable hydrogen bond acceptor character of squaramide. (C) 2000 Elsevier Science Ltd. All rights reserved.

引用

页码：2001 / 2005

页数：5

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