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DOI: 10.1055/s-0032-1316737
Some Practical Methods for the Application of 5-Metallo-1-benzyl-1H-tetrazoles in Synthesis
Publikationsverlauf
Received: 26. März 2012
Accepted after revision: 01. Juli 2012
Publikationsdatum:
17. August 2012 (online)
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Abstract
Nucleophilic reagents such as 5-lithiotetrazoles are synthetically powerful tools for the installation of tetrazole functional groups, but they are of limited utility due to the instability of tetrazole-derived carbanions. Herein, we report practical methods for the generation and use of new 5-metallo-1-benzyl-1H-tetrazoles (M = K, MgX, ZnX) derived from either 1-benzyl-1H-tetrazole or 1-benzyl-5-bromo-1H-tetrazole. By varying the metal counterion, the tetrazole carbanion stability was improved. Potassium- and magnesium-derived reagents underwent additions to carbonyl compounds at –30 and –20 °C, respectively. The isolated yields (41–85%) from these and other reactions were comparable to those reported for 5-lithiotetrazoles at much lower temperatures (–78 to –98 °C).
Supporting Information
- for this article is available online at http://www.thieme-connect.com/ejournals/toc/synlett.
- Supporting Information
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References and Notes
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