Dramatic structural effects of a single hydrogen atom in HNPBu t 3.
The molecular structure of tri-tert-butylphosphine imide has been re-determined using the recently developed DYNAMITE method, which allows all assumptions about local symmetry to be removed without increasing the number of refining structural parameters excessively. The imide hydrogen causes the NPBu(t)(3) group to deviate hugely from local C(3) symmetry, with N-P-C angles returned as 99.2(9), 110.9(7), and 111.5(11) degrees, while the C-P-C angles also deviate from symmetry, being 109.8(8), 110.5(9), and 113.9(9) degrees, so that the NPC(3) fragment is close to C(s) rather than C(3) symmetry. The application of the DYNAMITE method to HNPBu(t)(3) also allows the methyl groups to be asymmetric, which has been shown to be important by ab initio methods. The re-determination of this structure using these more sophisticated methods has also resulted in a much shorter P-N bond than was previously determined, and is consistent with the molecule being regarded as HN=PBu(t)(3), rather than HN(-)-P(+)Bu(t)(3).
Hinchley
Sarah L
SL
School of Chemistry, University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, Scotland, U.K.
Haddow
Mairi F
MF
Rankin
David W H
DW
D005740:Gases; D006859:Hydrogen / Q000737:chemistry*; D007094:Imides / Q000737:chemistry*; D008854:Microscopy, Electron / Q000379:methods; D008956:Models, Chemical; D010720:Phosphines / Q000737:chemistry*
D005740:Gases; D007094:Imides; D010720:Phosphines; C500104:tri-tert-butylphosphine imide; D006859:Hydrogen