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Synthesis 2013; 45(5): 683-693
DOI: 10.1055/s-0032-1316849
paper
© Georg Thieme Verlag Stuttgart · New York

Iodoacetic Acid is an Efficient Reagent for the Synthesis of Amino Acid Derived 2-Aminobenzimidazoles

Andrejs Krasikovs
a   Latvian Institute of Organic Synthesis, Aizkraukles 21, 1006 Riga, Latvia   Fax: +371(6)7550338   Email: edgars@osi.lv
,
Vita Ozola
a   Latvian Institute of Organic Synthesis, Aizkraukles 21, 1006 Riga, Latvia   Fax: +371(6)7550338   Email: edgars@osi.lv
,
Scott L. Dax
b   Galleon Pharmaceuticals, 213 Witmer Road, Horsham, PA 19044, USA
,
Edgars Suna*
a   Latvian Institute of Organic Synthesis, Aizkraukles 21, 1006 Riga, Latvia   Fax: +371(6)7550338   Email: edgars@osi.lv
› Author Affiliations
Further Information

Publication History

Received: 29 November 2012

Accepted after revision: 07 January 2013

Publication Date:
06 February 2013 (online)

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Abstract

Chiral, nonracemic, N-unprotected amino acids were converted into the corresponding N-benzimidazol-2-yl derivatives by a sequential procedure involving initial formation of isothiocyanates, their reaction with arene-1,2-diamines, and cyclization–desulfurization­ of the intermediate thioureas with iodoacetic acid. The simplified workup and the lack of volatile or toxic byproducts in the key desulfurization step renders iodoacetic acid a superior reagent to the usual reagent, iodomethane.

Key words

amino acids - cyclization - desulfurization - green chemistry - heterocycles

Supporting Information

    for this article is available online at http://www.thieme-connect.com/ejournals/toc/synthesis.
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