Synthesis and structural characterization of (4,7-dioxaoctyl)phenyldichlorostannane and triphenyltin compounds containing various polyoxaalkyl moieties

The synthesis and characterization of (4,7-dioxaoctyl)triphenyltin (1), (4, 7,10-trioxaundecyl)triphenyltin (2), (4,7,10,13-tetraoxatetradecyl)tripheny ltin (3), and (4,7-dioxaoctyl)phenyldichlorostannane (4) are reported. Inve stigatons using H-1-, C-13-, and Sn-119-NMR, gradient assisted 2D H-1-C-13 HMBC and HMQC NMR, 1D H-1-Sn-119 HMQC NMR demonstrate that 1-3 are essentia lly tetracoordinated. By contrast, the structure of compound 4, determined by X-ray diffraction methods, reveals a hexacoordinated, distorted octahedr al geometry, in which the 4,7-dioxaoctyl ligand is tridentate, with a facia l arrangement of the C, O, O atoms with respect to tin. NMR investigations reveal that this structure exists in solution, but is labilized by a double ring opening-closing mechanism. (C) 2001 Published by Elsevier Science B.V .