Browse by author
Lookup NU author(s): Dr Keith Izod,
Dr Ewan Clark,
Emeritus Professor Bill CleggORCiD,
Dr Ross Harrington
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
The reaction between PhPCl2 and 1 equiv of RLi, followed by in situ reduction with LiAIH(4) and an aqueous workup yields the secondary phosphane PhRPH [R = (Me3Si)(2)CH]. Treatment of PhRPH with n-BuLi in diethyl ether generates the lithium phosphanide (RPhP)Li(Et2O)(n) [15(Et2O)], which may be crystallized as the tetrahydrofuran (THF) adduct (RPhP)Li(THF)(3) [15(THF)]. Compound 15(Et2O) reacts with 1 equiv of either NaO-tBu or KO-tBu to give the corresponding sodium and potassium phosphanides (RPhP)Na(Et2O)(n) (16) and (RPhP)K(Et2O)(n) (17), which may be crystallized as the amine adducts [(RPhP)Na(tmeda)](2) [16(tmeda)] and [(RPhP)K(pmdeta)](2) [17(pmdeta)], respectively. The reaction between 2 equiv of 17 and GeCl2(1,4-dioxane) gives the dimeric compound [(RPhP)(2)Ge](2)center dot Et2O (18 center dot Et2O). In contrast, the reaction between 2 equiv of 15 and SnCl2 preferentially gives the ate complex (RPhP)(3)SnLi(THF) (19) in low yield; 19 is obtained in quantitative yield from the reaction between SnCl2 and 3 equiv of 15. Crystallization of 19 from n-hexane/THF yields the separated ion pair complex [(RPhP)(3)Sn][Li(THF)(4)] (19a); exposure of 19a to vacuum for short periods leads to complete conversion to 19. Treatment of GeCl2(1,4-dioxane) with 3 equiv of 15 yields the contact ion pair (RPhP)(3)GeLi(THF) (20), after crystallization from n-hexane/THF. Compounds 15(THF), 16(tmeda), 17(pmdeta), 18 Et2O, 19a, and 20 have been characterized by elemental analyses, multielement NMR spectroscopy, and X-ray crystallography. While 15(THF) is monomeric, both 16(tmeda) and 17(pmdeta) are dimeric in the solid state. The diphosphagermylene 18 center dot Et2O adopts a dimeric structure in the solid state with a syn,syn-arrangement of the phosphanide ligands, and this structure appears to be preserved in solution. The ate complex 19a crystallizes as a separated ion pair, whereas the analogous ate complex 20 crystallizes as a discrete molecular species. The structures of 19 and 20 are retained in non-donor solvents, while dissolution in THF yields the separated ion pairs 19a and [(RPhP)(3)Ge][Li(THF)(4)] (20a).
Author(s): Izod K, Stewart J, Clark ER, Clegg W, Harrington RW
Publication type: Article
Publication status: Published
Journal: Inorganic Chemistry
Print publication date: 14/04/2010
ISSN (print): 0020-1669
ISSN (electronic): 1520-510X
Publisher: American Chemical Society
Altmetrics provided by Altmetric