Reaction of N‐thioamido amidines with phosphoramide derivatives: Synthesis of 2‐substituted‐1,3,5,2‐triazaphosphorines

The reaction of N-thioamido amidines 1 with tris(dimethylamino)phosphine or bis(diethylamino)phenylphosphine in refluxing toluene leads to the 1,3,5,2λ3-triazaphosphorines 2 and 3, respectively. The condensation results in the release of two molecules of dialkylamine. The sulfuration of the trivalent phosphorus atoms was achieved by the reaction with elemental sulfur, followed by heating in toluene. The structure of the triazaphosphorines 2 and 3 and their thione derivatives 4 and 5 were readily elucidated by means of 1H, 13C, and 31P NMR spectroscopy and mass spectrometry. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:272–277, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20546