Matthew G. Donahue, Nicholas G Jentsch, C. Simons
Apr 26, 2017
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Influential Citations
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Citations
Journal
Tetrahedron Letters
Abstract
Abstract The synthesis of [ 13 C 6 ]3,4-diaminobenzoic acid from commercially available [ 13 C 6 ]aniline is described in six steps. Salient features of this route include the preparation of a differentially protected 3,4-diaminobenzonitrile, hydrogen gas free aromatic nitro group reduction with ammonium formate and facile benzimidazole ring closure of the ortho -arylenediamine with triethylorthoformate. This stable-labeled 3,4-diaminobenzoic acid is an ideal [M+6]isotopomer to synthesize complex benzimidazole fragments for mass spectrometry internal assays.