Synthesis 2016; 48(02): 263-270
DOI: 10.1055/s-0035-1560639
paper
© Georg Thieme Verlag Stuttgart · New York

A New Approach to the Synthesis of 1-Arylbenzimidazole-2-thiones from Nitroarenes and Anilines through Halogen-Free Substitution of Hydrogen via Iminophosphorane Intermediates

Emilia Łukasik
Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland   Email: zbigniew.wrobel@icho.edu.pl
,
Zbigniew Wróbel*
Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44, 01-224 Warsaw, Poland   Email: zbigniew.wrobel@icho.edu.pl
› Author Affiliations
Further Information

Publication History

Received: 09 July 2015

Accepted after revision: 08 September 2015

Publication Date:
30 September 2015 (online)


Abstract

2-(Arylamino)phenyliminophosphoranes, formed directly from 2-nitrosodiarylamines, undergo a high-yielding cyclocondensation with CS2, providing a variety of 1-arylbenzimidazole-2-thiones. The reaction concludes a new synthetic route leading to the title compounds from simple nitroarenes and arylamines. The protocol is superior to common methods that use N-arylarylenediamines because it omits the SNAr substitution of halogen atoms in ortho-halonitroarenes, as well as reduction processes required for the synthesis of the intermediate diamines.

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