Issue 16, 2004

The molecular structure of tetra-tert-butyldiphosphine: an extremely distorted, sterically crowded molecule

Abstract

The molecular structure of tetra-tert-butyldiphosphine has been determined in the gas phase by electron diffraction using the new DYNAMITE method and in the crystalline phase by X-ray diffraction. Ab initio methods were employed to gain a greater understanding of the structural preferences of this molecule in the gas phase, and to determine the intrinsic P–P bond energy, using recently described methods. Although the P–P bond is relatively long [GED 226.4(8) pm; X-ray 223.4(1) pm] and the dissociation energy is computed to be correspondingly small (150.6 kJ mol−1), the intrinsic energy of this bond (258.2 kJ mol−1) is normal for a diphosphine. The gaseous data were refined using the new Edinburgh structure refinement program ed@ed, which is described in detail. The molecular structure of gaseous P2But4 is compared to that of the isoelectronic 1,1,2,2-tetra-tert-butyldisilane. The molecules adopt a conformation with C2 symmetry. The P–P–C angles returned from the gas electron diffraction refinement are 118.8(6) and 98.9(6)°, a difference of 20°, whilst the C–P–C angle is 110.3(8)°. The corresponding parameters in the crystal are 120.9(1), 99.5(1) and 109.5(1)°. There are also large deformations within the tert-butyl groups, making the DYNAMITE analysis for this molecule extremely important.

Graphical abstract: The molecular structure of tetra-tert-butyldiphosphine: an extremely distorted, sterically crowded molecule

Article information

Article type
Paper
Submitted
26 May 2004
Accepted
14 Jun 2004
First published
06 Jul 2004

Dalton Trans., 2004, 2469-2476

The molecular structure of tetra-tert-butyldiphosphine: an extremely distorted, sterically crowded molecule

S. L. Hinchley, H. E. Robertson, K. B. Borisenko, A. R. Turner, B. F. Johnston, D. W. H. Rankin, M. Ahmadian, J. N. Jones and A. H. Cowley, Dalton Trans., 2004, 2469 DOI: 10.1039/B407908F

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements