Synthesis of organophosphorus compounds containing different Y,C,Y-chelating ligands. Crystal structure of P ← N intramolecularly coordinated diselenoxophosphorane

The reactions of L1–3Li salts containing different Y,C,Y-chelating ligands L1 = 2,6-(t-BuOCH2)2C6 H 3 - 1 , L2 = 2,6-(MesOCH2)2C6 H 3 - 1 and L3 = 2,6-(Me2NCH2)2C6 H 3 - 1 with PCl3 is reported. While the presence of ligands L2,3 afforded the synthesis of dichlorophosphines L2PCl2 (2) and L3PCl2 (3), the use of ligand L1 resulted to the isolation of O → P coordinated 1-chloro-7-(t-butoxymethyl)-3H-2,1-benzoxaphosphole (1) as the result of the cyclization type reaction of dichlorophosphines L1PCl2. The hydrolysis of compounds 1–3 as well as the preparation of phosphanes L2PH2 (7), L3PH2 (8), L2PH(SnMe3) (9) and L3PH(SnMe3) (10) is also discussed. The presence of N → P coordination enabled the isolation of N → P coordinated diselenoxophosphorane L3PSe2 (11). Compounds 1–11 were characterized by the help of multinuclear NMR spectroscopy, ESI mass spectrometry and the structure of compound 11 was established by X-ray diffraction analysis.