{"id":9486,"date":"2011-03-07T16:27:56","date_gmt":"2011-03-07T15:27:56","guid":{"rendered":"https:\/\/web.computaex.es\/?page_id=9486"},"modified":"2025-08-27T09:13:58","modified_gmt":"2025-08-27T07:13:58","slug":"mechanistic-insights-on-azide%e2%88%92nitrile-cycloadditions-on-the-dialkyltin-oxide%e2%88%92trimethylsilyl-azide-route-and-a-new-vilsmeier%e2%88%92haack-type-organocatalyst","status":"publish","type":"page","link":"https:\/\/computaex.es\/en\/publicaciones\/mechanistic-insights-on-azide%e2%88%92nitrile-cycloadditions-on-the-dialkyltin-oxide%e2%88%92trimethylsilyl-azide-route-and-a-new-vilsmeier%e2%88%92haack-type-organocatalyst\/","title":{"rendered":"Mechanistic Insights on Azide\u2212Nitrile Cycloadditions: On the Dialkyltin Oxide\u2212Trimethylsilyl Azide Route and a New Vilsmeier\u2212Haack-Type Organocatalyst"},"content":{"rendered":"
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David Cantillo, Bernhard Gutmann, and C. Oliver Kappe:\u00a0Mechanistic Insights on Azide\u2212Nitrile Cycloadditions: On the Dialkyltin Oxide\u2212Trimethylsilyl Azide Route and a New Vilsmeier\u2212Haack-Type Organocatalyst<\/strong>. The Journal of Organic Chemistry. 7 Marzo, 2011.<\/p>\n

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Abstract<\/span><\/h2>\n
\"Abstract<\/div>\n<\/div>\n
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The mechanism of the azide\u2212nitrile cycloaddition mediated by the known dialkylltin oxide\u2212trimethylsilyl azide catalyst system has been addressed through DFT calculations. The catalytic cycle for this tin\/silicon complex-based mechanism has been thoroughly examined, disclosing the most plausible intermediates and the energetics involved in the rate enhancement. In addition, a new catalyst, 5-azido-1-methyl-3,4-dihydro-2H<\/i>-pyrrolium azide, is presented for the formation of tetrazoles by cycloaddition of sodium azide with organic nitriles under neutral conditions. The efficiency of this organocatalyst, generated in situ from\u00a0N<\/i>-methyl-2-pyrrolidone (NMP), sodium azide, and trimethylsilyl chloride under reaction conditions, has been examined by preparation of a series of 5-substituted-1H<\/i>-tetrazoles. The desired target structures were obtained in high yields within 15\u221225 min employing controlled microwave heating. An in depth computational analysis of the proposed catalytic cycle has also been addressed to understand the nature of the rate acceleration. The computed energy barriers have been compared to the dialkylltin oxide\u2212trimethylsilyl azide metal-based catalyst system. Both the tin\/silicon species and the new organocatalyst accelerate the azide\u2212nitrile coupling by activating the nitrile substrate. As compared to the dialkylltin oxide\u2212trimethylsilyl azide method, the organocatalytic system presented herein has the advantage of higher reactivity, in situ generation from inexpensive materials, and low toxicity.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n

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Fuente de la publicaci\u00f3n:<\/div>\n
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