Unexpected Course of the Reaction of 2‐Unsubstituted 1H‐Imidazole 3‐Oxides with Ethyl Acrylate |
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| Authors: | Grzegorz Mlostoń Katarzyna Urbaniak Anthony Linden Heinz Heimgartner |
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| Institution: | 1. University of ?ód?, Department of Organic and Applied Chemistry, Tamka 12, PL‐91‐403 ?ód?, (phone: +48?42?6355761;2. fax: +48?42?6655162);3. Organisch‐chemisches Institut der Universit?t Zürich, Winterthurerstrasse 190, CH‐8057 Zürich, (phone:+41?44?6354282;4. fax: +41?44?6356812) |
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| Abstract: | The attempted ethenylation at C(2) of 2‐unsubstituted 1H‐imidazole N‐oxides with ethyl acrylate (=prop‐2‐enoate) in the presence of Pd(OAc)2 does not occur. In contrast to the other aromatic N‐oxides, the 2+3] cycloaddition of imidazole N‐oxides predominates, and 3‐hydroxyacrylates, isomeric with the cycloadducts, are key products for the subsequent reaction. The final products were identified as dehydrated 2+1 adducts of 1H‐imidazole N‐oxide and ethyl acrylate. The role of the catalyst is limited to the dehydration of the intermediate 3‐hydroxypropanoates to give 1H‐imidazol‐2‐yl‐substituted acrylates. |
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| Keywords: | Cycloadditions 1H‐Imidazole 3‐oxides Acrylate ethyl |
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