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超快的多序光化学的5-diazo Meldrum 的酸

Philipp Rudolf1, Johannes Buback, Jochen Aulbach

  • 1Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.

Journal of the American Chemical Society
|October 15, 2010
PubMed
概括

这项研究使用先进的光谱学揭示了5-diazo Meldrum的酸 (DMA) 复杂的光诱导反应. 研究人员确定了多个光产物和反应途径,提供了对DMA光化学的见解.

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The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para position.
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Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.
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