Oligosubstituted Pyrroles Directly from Substituted Methyl Isocyanides and Acetylenes |
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Authors: | Alexander V Lygin Dipl‐Chem Oleg V Larionov Dr Vadim S Korotkov Dipl‐Chem Armin de Meijere Prof Dr |
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Institution: | Institut für Organische und Biomolekulare Chemie, Georg‐August‐Universit?t G?ttingen, Tammannstrasse 2, 37077 G?ttingen (Germany), Fax: (+49)?551‐399‐475 |
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Abstract: | The formal cycloaddition of α‐metallated methyl isocyanides 1 onto the triple bond of electron‐deficient acetylenes 2 represents a direct and convenient approach to oligosubstituted pyrroles 3 . The scope and limitations of this reaction (24 examples, 25–97 % yield) are reported along with an optimization of the reaction conditions and a rationalization of the mechanism. In addition, a related newly developed CuI‐mediated synthesis of 2,3‐disubstituted pyrroles by the reaction of copper acetylides derived from unactivated terminal alkynes with substituted methyl isocyanides is described (11 examples, 5–88 %yield). |
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Keywords: | catalysis copper cycloaddition isocyanides pyrroles |
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